The bans are not automatic, People usually Post in the general section;
General - MPGH - MultiPlayer Game Hacking
Or contact a Mod/GMOD/SA To ban them.
IF you are caught to skip a post ban you could be banned for a longer time as this is "Ban Evasion".
The idea is, When you reach these Post amounts you deserve a "Vacation" From MPGH , Usually Bans last from 1-3 Days. Hope this helps.