Destructive Split audio events

In the track view you can split the audio events on the grid so all tracks are split in the same place, unfortunately you can’t discard the unwanted audio here so I have 1hr 20mins unused audio per track which is wasting a lot of space on the iPad

In the audio editor you CAN discard unwanted audio and delete it from the iPad’s storage but there’s no grid so you can’t edit them all to the same length, this throws the tracks out of sync

I need to flush unused audio in the event view to clear it from storage but this can only be done in the audio editor where there is no way of editing the tracks to the same length

Perhaps the only way is to mixdown each track to a separate wav and re-import them one at a time, then delete the originals ?