This question already has an answer here:
I upvoted an answer, and remained on the page and read a few more answers, while noticing that the user that I originally upvoted made several edits. I later noticed something from one of the edits that made me want to remove my upvote, but I got the message: "You last voted on this message 6 minutes ago. Your vote is now locked unless the answer is edited."
I noticed that no edits were indicated, so they must have taken place during the grace period.
This was not a case of me rushing or misreading, the answer originally posted was fine. An edit was made during the grace period. I went back 6 minutes after I upvoted, saw something that I didn't approve of appended to the original answer and wanted to change my vote, but couldn't.
To clarify, I understand that this is status-bydesign; I am NOT trying to report a bug. I am requesting that a feature be implemented such that this situation can be resolved without having to resort to making a fake-edit and a following rollback.
Potential Solution: Perhaps votes that occur during the grace period should simply not be locked-in.