From what I know the "alt account" rule only comes when both the main account and the alt account is enrolled in the same campaign however if one user only has one account enrolled in one campaign even if its an alt then it's still allowed without any kind of violation whatsoever. Having an alt account isn't a violation in itself, however having two accounts in the same campaign would just be considered as cheating the campaign. Below are some of the campaign rules I know about alt accounts being enrolled in a sig campaign.