Anytime but heres a few things
1. The mods get pissed off if you make a thread only to raise post count
2. The post count highers to get a better rank so i think after you get your first 20 you become a rookie poster then you have to get 60 to become something else or something like that
3. Dont go into Old forums just to post there and get your post count up, it pisses the mods off and you dont wanna be banned now do you?
4. DONT SPAM IN IMPORTANT THREADS TO GET POST COUNT UP
I believe the only place you can really spam in is web-families, mods dont really mess with anything unless asked there