Please reference this edit for details on this submission:
https://beta.musicbrainz.org/edit/40984327

Disc IDs were added to the mediums of a digital format release. This resulted in receiving this message when attempting to make further edit to the release:
"This medium has a disc ID, pregap track, or data track, so you can only change the format to one that can have disc IDs"

This message prompts the edit to fix the issue that a digial media release has a Disc ID assigned to it. This is reactive, where a proactive approach would be to prevent a Disc ID from being added to a digital format release, and possibly requiring the format to already be assigned to one that allows for a Disc ID.