PCs are removed from readers of single blind submissions

[nlbahy]

In single blind venues, if a PC edits a submission after the deadline, they are removed from the readers of the submission.

[melisabok]

I don't think the single blind submission can be edited using the edit button after the deadline. The readers field is changed to the values-regex so we can define the readers of each submission, for example: PCs, PaperX/Reviewers, PaperX/Authors.

The UI renders the values-regex field as a textbox, we need to see what happens when the note is edited, the values should remain the same if the user doesn't change them.

Another alternative es to create a revision invitation for the PCs only, so they can edit the paper at anytime and the history record is preserved.