As of today, every participant that has been a part of the signature campaign can remove his/her signature without any repercussions.
As for Twitter Bounty stakes and its calculation, here are some insights.
Maximum number of retweets for period 1 to period 5 is 28 (max 2 retweets per day times 14 days equals 28). Everybody who exceeded this number will have only 28 stakes, no more. For period 6 maximum is 10 (max 2 retweets per day times 5 days equals 10).
As for minimum number of retweets for period 1 to 5 it is 6 retweets. Every user that has 5 or less, he/she will not be eligible for the bounty in that particular period. For period 6 minimum is 3, because it lasted only 5 days.
The signature can finally be cancelled, but is your real calculation correct? You have not calculated the final moment of the end of ICO, and you are openly violating the rules of the original project, so you are a dishonest project!