My alt account got message "
Sorry **, you are banned from posting or sending personal messages on this forum.
Insubstantial posts+sig ad (14 days)"
What does it mean? When can I post from my account?
This is normal to the signature campaign spammers to boost up their post count. I do not see the point of creating multiple accounts just for the purpose of doing simultaneous sig campaign when you can just focus on one and join a campaign that has no limits on the posts.
Did one of your other accounts get banned? If so then you should treat it as if all of your accounts are banned. The account that was banned was most likely the one that was making the shitposts, however if it is determined that you are posting from another account then it is likely that your other accounts will have an increased "punishment" (from what I have heard double the punishment, so either a 28 or 30 day ban).
The only exception to this rule is it you are trying to appeal your ban (although I have seen people open scam accusations while banned as well - this would still technically be against the rules though).
I think you are referring to ban evasion? I'm not quite sure with the ban period though.