Quick question about max battle points

[Wdll]

I remember there is a max (for say long random campaigns) that beyond that while it is possible to set it, it is not advisable because of some...something about something.
Anyway, I think the "limit" is about 20K or 25K? Am I anywhere near?
The reason I am asking is because I haven't played the game in a long while and I want to do a let's play for my youtube channel and I rather have some basics right from the very beginning.