Plex deleting episodes

To add to FordGuy61,

copy some episodes to a separate area.
play with them , renaming a few at a time
gain more confidence.

As you get more confident, you’ll find you end up taking a whole bunch (25-50) at a clip. On my slow internet, that translates to about 1 minute per block of 50 (full series). With 1500 (1500/50 = 30), and a proper renaming template, 30 minutes work at best, probably 1 hr maximum inclusive of learning time.

My TV series are stored under /nas/tv
My FileBot renaming rule is therefore /nas/tv/{n}/Season {s.pad(2)}/{n} - {s00e00} - {t}

where:

  {n} = name.
  {s} = season number,
  pad(2) = padded with leading zero to 2 digits,  
  {t} = episode title

If FileBot sees any ambiguities, it will ask for resolution as it matches.
If there are illegal characters in the naming, it will confirm permission to clean it up prior to renaming .
If there are collisions (destination file), it will so state and allow you to skip it (remove from the renaming list).