[NoOne]

Hangs in september? i bet it's the end of season stuff for MiL leagues / call-ups if those are around in 1947. you can look to spread it out per league or make it all happen on one day based on scheduels/start dates etc.

if it's localized to one time period, it's probably not completely avoidable. if it is specific days it slows down but not other days shortly after/before, this is likely the cause.

if not...

try to see what is different between the two leagues... try anything new?

if MiL is active in 1947 but not 1900, it could be this, but i doubt it would slow it down as much as you mention (before i saw specific september comment). check MiL stats and AI settings -- make sure it isn't set to 'force results' or similar checkbox verbage. that can make things a crawl (whole season, not 1 month).

if it's just processing related -- turn some thigns to ondemand - like pictures, and anything you can recreate with boxscores/gamelogs etc... it won't be lost and it'll generate so fast when you click you won't notice in most cases.. as opposed to thousands generated automatically that you'll never look at.

on demand wpa graphs instead of automatically creating them every single game, for example. typically the mouseover tip lets you know if it can be recreated from logs/boxscores and what is required to be enabled for that to occur.

stats and ai settings -- if you don't do much with mil, turn stats tracking down to "low detail" - has to be done for each mil league in dropdown selection box. even turn off awards or playoffs. something to think about for AAA and call-ups even if it doesn't solve problem.

edit: the threads settings may require a restart of the application... not likely a reboot of compuer, but not entirely unheard of, either.