1,447,160 shs 484.95. Jim forgot about this odd lot in a smaller account?

I don't know the origin of the transaction you're talking about, but I assume it's a change in some portfolio somewhere? maybe a sub's retirement fund? Not related to the stock repurchase program, anyway, since those are explicitly documented.

Looking only at B shares:
There haven't been any B shares bought under the repurchase program since November 2023 at $347.16. The highest absolute price paid to date (average in a month) for a B share under the repurchase program has been $357.22 in Sept 2023. Highest price-to-known-book-at-start-of-month price paid for a month's block of B shares has been 1.480 in Feb 2022.

To repeat, all of those are figures for B shares only. Management has a clear preference for repurchases of A shares over B, and some (I believe most) of the most recent months of A purchases at higher valuations were from long time shareholders for non-economic reasons, so for both reasons one should not try to convert any A share purchase price by 1500 to get an idea of what management thinks a B share is worth.

Unless/until P/B starts to mean something meaningfully different as a quick yardstick for value, I see no reason to think that management would purchase a B share at over 1.48 times book (known and published peak-to-date book per share at the beginning of the month in question) in order to add to the value of remaining shares, for the simple reason that they haven't done so.

Jim