While I did transfer my save from OOTP18 on the first day of the off-season, I simply couldn't resist and wait for at least the first patch, before I would go on

So I met two very small cosmetic issues with my winter leagues:
1) The players on the winning team of a winter league are credited with an incorrect team in their personal histories; in the history, there is not the name of the winter league team, but the parent team from which they are loaned.
2) The total attendance on winter league team history index for a given year (in my case the last year - previous years ran in OOTP18) is given as 0. It is computed correctly throughout the season, it changed to 0 only at the end of the winter league season.
The game is fantastic. I'm so glad I have to report just such unimportant nitpicks

Oh well, back to my off-season team evaluation...