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.
Hey yombu have a conscience go and correctly calculate the number of messages made by the members of the signature bounty they spent their time and work on advertising this big project Envion and you can not even count the number of messages bounty members.