The question can be split into two parts:
1. Best time during a given year
2. Best year
1. In theory, the best time within a year to convert is when your T-IRA portfolio is at its nadir. Which is great if you can see into the future.
Pragmatically, waiting until there's a market correction (10% dip or more) can leave you converting at a higher value than converting now. If the market rises 15% while you're waiting and then drops 10% (to 103.5% of your starting value), what's the point? Or if you're planning on converting a bit each year, you can easily wind up stuck at the end of the year with a higher market still waiting for that correction.
If you're trying to keep MAGI under a certain "cliff" threshold (e.g. for ACA subsidies or to avoid IRMAA) then you should likely be conservative and top off your conversion near year end once you have a better handle on MAGI YTD. If your concern is about edging into another tax bracket, it's not a big deal if you wind up a few dollars over or under, so don't wait until year end for that reason.
2. If you're converting and paying taxes with non-IRA money, sooner can be better than later even if your expected tax rates in the future will be a little higher. That's because you're effectively adding money to your IRA by prepaying your taxes. (A dollar in a Roth is worth more than a dollar in a T-IRA.)
OTOH, many states give tax breaks for retirement income (including Roth conversions) once one reaches a certain age. So it can be advantageous to wait until then. You might convert between the time you reach that age and the time you retire and actually start drawing money from your T-IRA and/or pension (and possibly using up that tax break).
Several states give some sort of help on Medicare Part D prescriptions, where your income needs to be low enough to qualify. Doing Roth conversions earlier (even at somewhat higher tax rates) may help qualify for these or other income-related programs.
The largest such program is EPIC in NYS. Its income cutoff is decidedly middle class: $75K single, $100K married.
The rule of thumb short answer is the sooner the better (both within year and across years); just don't do too much in a single year and keep various income thresholds in mind. And if you're thinking of making charitable contributions, keep some money in the T-IRA so you have it available for QCDs.

Gentlemen, I really appreciate for your inputs. Last spring was a great opportunity to do a large conversion. Unfortunately many of us did not plan for it. Now we are evaluating which how much and which funds to convert per year. Great reminder that the tax table is for the adjusted gross income.
To reduce tax in retirement, we did few small changes. We switched our 401(K) to Roth 401(K) several years ago. Still we have rollover and traditional IRAs to consider for higher future tax and RMD. Higher retirement income incurs additional cost on Medicare premium and taxation on most of the social security benefit.

Given his cryptocurrency remarks, I'm reminded of the Simpsons meme of "Old Man Yells At Cloud"...... how many US Dollars have been used for illicit purposes over the years? Just because something is new and/or misused (or not understood) by some doesn't mean it's necessarily a bad thing.
Listening to Munger's pomposity bubbling just under the surface in his remarks in recent years, I'm reminded of the Wall Street saying that "past performance not indicative of future results."
BTW, anyone ask how his BABA stake is doing these days?
PS: I do agree w/Munger that the markets are 'crazy' and imo have been that way since the GFC.

There is already a transition place in place for a number of years including Greg Abel, Ajit Jain, and Todd Combs. I believe Abel is the one responsible for investing in Apple and dumped IBM (a long holding for many years). Now Apple accounts for over 40% of BRKA portfolio.
https://barrons.com/articles/who-succeed-berkshire-hathaway-ceo-warren-buffett-51577375291

It is incredible that Munger is 97 years old and he is very sharp. BRKB has not made big purchases lately other than buyback of their own stock.

Frankly, and based solely on the first chart itself (which I also expanded to cover almost four years), I'm not really seeing ANY usable relationship between the two things. What little (inverse) relationship MAY exist seems to come too late to be of any use. I've seen this "VIX predicts the market" idea before, but I don't see anything here to bolster that argument. What am I missing?

Came across this one today. It’s being suggested by some pundits as a hedge against your gold mining stocks falling further.
The description from Lipper:
“The Fund seeks daily investment results, before fees and expenses, of 200% of the inverse (or opposite) of the price performance of the NYSE Arca Gold Miners Index. The Fund creates short positions by investing at least 80% of its net assets in: futures contracts; options on securities, indices and futures.”
DUST is off -71% over the past 3 years. Think I’d rather fry along with some mining stocks than try to catch this one. Gold’s been in a see-saw all year, bouncing between $1700 and around $1850. It appears to be on its way down again after topping-out only a few weeks ago.Just below $1800 at present. But this kind of erratic behavior is pretty typical. Limit your exposure. Don’t chase on the way up or down.

My best friend of over 50 years I met as a roommate my first year at CMU in ‘65. Both in our late 70s now, we sometimes contemplate the unthinkable. “With all its sham, drudgery and broken dreams, it is still a beautiful world. Be cheerful. Strive to be happy.”

https://www.mutualfundobserver.com/2021/12/
“I learned this morning that my best friend of nearly 50 years, Nicholas Burnett, professor emeritus at Sacramento State, was being removed from life support.”
Sorry to hear of your loss David.

The VIX (Volatility Index) is closing in on 30 this AM. We touched above this level one year ago (Nov. 30, 2020) when we briefly reach the 33 level.
Here's a chart of the VIX showing it's movement over the last 5 years along with the S&P 500.

Speaking of DKNG - I track it and it’s off 6.75% for the day at $32 plus change. Reports are Cathie bought a truck load at $43-$44 a few weeks ago - Whew! Here’s a stock that’s seen close to $75 within the past year. I think it was launched couple years ago as part of a a “SPACK”. Getting spanked today for whatever reason. No idea what the trouble is. But harmed by the market saturation with too many competing plus the steep taxes states are hitting them with.
Additional Thoughts - The stock has been subject to short selling pressure during past year. And now, with SARK opening, that pressure is probably even greater. Nuts. If Cathie buys a stock, it’s got a target on its back. :) Top institutional holders Vanguard and T. Rowe Price. I’d think safer to own it through a small cap fund.

I have managed to restore several of my accounts by
1) ensuring that "Schwab" is listed as the brokerage name, not "zz-Schwab" or zzz-Schwab" on the account details window ( this is in the recommendations)
But this still would not allow me to "Activate" the accounts with the "Schwab brokerage" link, but there is another Schwab.com listed in the "add account" drop down menu
"Schwab Investor-C"
This seems to work for several of the accounts but not all
I am very discouraged by this disaster. As you mention, this is the worst snafu from Quicken in the 25 years I have been using it

If I may digest from the original post on EM small caps for a moment. There are still few EM opportunities still available in larger caps. I use NWFFX for a number of years as a lower risk EM fund. The broader mandate allow companies that derive majority of their revenue from EM including Microsoft.
https://morningstar.com/articles/975441/go-active-in-emerging-markets

Article appears in today’s (November 29) Financial Times.
Link is for an alternate source which may be more accessible.
Title is taken from the FT.
Bylines: Hudson Lockett & Tabby Kinder

I'm inclined to agree with @Baseball_Fan that multi-strategy funds are generally a bunch of spaghetti.
Even if one does understand how each alternative strategy tends to work in isolation and even if one does understand how they interact, IMHO two wildly optimistic assumptions, one still does not have any sense of how they are being allocated/used. A fund saying that it "seeks to provide total return ... in both periods of strong returns and periods of market stress" tells me almost nothing about how it uses those alternative strategies.
More studying of a fund may not make it any clearer. M* gave DBLTX a "not rated" mark for two years (2014-2016) because "when ... evaluating sophisticated bond strategies like DoubleLine Total Return Bond, publicly available information often does not suffice."
https://www.morningstar.com/articles/759331/why-were-moving-doubleline-total-return-bond-funds-rating-to-neutral
Yet for most of us peons, public info is all we have to work with. And it's hard to deny that funds like BAMBX are employing sophisticated strategies, bond and other. FWIW, M* decided to change the rating of DBLTX from "not rated" to "neutral" because M* felt it was more informative to say that based on what they knew they could not recommend the fund ("neutral") than to say nothing.
With respect to the BAMBX's portfolio, Lipper is showing net allocations. According to M*, the fund is comprised of 65% short positions and 165% long, which adds up to 100% of the portfolio, net. A lot of shorting going on.
At a superficial level (i.e. just looking at the 165/65 figure), this looks like the 130/30 funds of a decade ago on steroids. Except that for BAMBX that's just a summary of its holdings and not its strategy. Here's a M* piece on the 130/30 funds of yesteryear, and the risks they carried.
https://www.morningstar.com/articles/287718/article
TMSRX is net 48% long in fixed income and net 6% short in equity, both of which should have helped its performance Friday, yet it dropped ½%. It's not so easy to figure out what these sorts of funds are doing. Even less so for BAMFX with a 500% turnover rate.

So you're going to put your monies into something like that based on one day's performance? [...]
Your money, do with it what you feel is best for you. This fund is not for me. Been burned by iqdax,. Learning my lesson.
I wish you good investing and good luck @fred495
Baseball Fan

What am I missing? There was nothing in my comment about BAMBX's performance record over the past five years that would indicate I was going to put my money into this fund. I would certainly never purchase any fund based on one day's performance.
Seems you misunderstood the purpose of my posting, Fan.
Good luck,
Fred

(Lipper* generally quotes from the manager’s description):
“The Fund seeks total return comprised of current income and capital appreciation. BlackRock will invest the Funds assets through a diversified set of strategies that seek to provide total return comprised of current income and capital appreciation in both periods of strong returns and periods of market stress.”
77% in bonds likely reason the fund was up a bit yesterday. Longer dated high quality bonds were up sharply.
Since the asset breakdown on Lipper adds up to 100%, it’s unlikely they’re doing much (if any) shorting - which generally skews the total to something over 100.
I tend to like Blackrock. Rock Rieder, one of their fixed income people, talks a good game. Bright and articulate.
No fund is a “spaghetti bowl” if one is willing to invest the time and energy into exploring the contents. In the case of TMSRX I’ve not done the due diligence I probably should have, trusting in TRP whom I’ve been with for about 30 years to run that complex fund on the straight and narrow and not put my money at excessive risk. But that’s laziness on my part - not dereliction on theirs.
@Baseball_Fan - Could you share a little about your current investment approach? What do you like in addition to near 0% cash? I recall about 6-7 months ago you were buying Home Depot and also looking for inflation hedges. The problem with those inflation hedges is that a lot of other people caught the scent in the wind 6 months ago and chased. It’s a diverse lot. Some areas (certain industrial metals) are doing fine and may not be overpriced. But it’s a rough playing field as evidenced by the more than 6% drop in oil yesterday.
*Link to BAMBX Lipper profile: http://www.funds.reuters.wallst.com/US/funds/overview.asp?YYY622_6m0GgCfSF7IkKdT1pfwHShuZTH3KwZb8EX/lL+8rQLcR/QKIWm+VprdhsazlKneG

POAGX is closed to new investors for several years. Count yourself lucky if you already an investor. The other two PRIMECAP funds, Odyssey Growth Fund, POGRX and Odyssey Stock fund, POSKX are still open.

@bee - Thanks.
Obviously something is screwed up there. Note that for 1 year the fund ranks 25th among its peer group, while for 3 years it ranks much better - 7th. So I’ll guess they haven’t updated their numbers on the chart you pasted to reflect the current year’s lackluster performance.
However, if the fund’s potential “worst case” downside really is 65% as they claim, I’d suggest not buying it. Such a disastrous year would leave only 35% of the fund’ value remaining. Seems to me like you’d have to earn nearly 200% on that meager sum to get back to break-even the following year.
-
Added - I didn’t intend to recommend Ferris’ site. It’s just one of several I click on from time to time for a wide variety of views. Morningstar and Lipper are also helpful for broad overviews. For specific fund holdings and year-to year-performance it’s hard to top Yahoo. I buy very few new funds. Usually put candidates on a watch list and monitor for at least a few months before buying. MaxFunds seems to be the most critical in its assessments - for whatever reason.

Good point about insurance companies in general.
But I have personally seen an insurance RUN - Mutual Benefit Life (MBL). It was a provider in my 403b. My BIG mistake was that when I first heard the news of the run, I tried to alert out HR person in-charge. I should have joined the run instead. Oh well, my money was just frozen for half-dozen years. No money lost in an absolute sense, but only in the sense of opportunity costs.
I also learned how the state insurance programs work (or don't work). They certainly don't work like the FDIC insurance for failed banks.