Premiere transcoding in background?

Hi all,

Short version: Premiere seems to be transcoding footage in the background while the project is being worked on (???).

Long version: I created and finished a project for a game Announce trailer a few weeks ago, but due to my insane schedule, needed to get a (highly experienced) freelancer to edit the Gameplay trailer.

So I transcoded my Announce project (just in case she wanted any footage from it), but also created a new project with my Gameplay selects in it (created from whole, newly-captured files) popped the whole lot on a drive and sent it to her. One transcoded Announce project, one Gameplay project with whole files.

She opened my transcoded Announce project, imported my Gameplay selects and started editing from there.

This is where it gets weird...

To do an audio pass, I asked her to send me her Gameplay project file, which should just simply relink with the footage that is on my RAID. We've done this countless times before and it's always worked.

For some weird, bizarre, and downright unfathomable reason, where once we had whole files, we now have a load of Transcoded files ending in either .MOV.mov or .MOV_001.mov (in sequential numbers)

She has not transcoded her project, so where on earth are these shortened, transcoded files coming from?

We're both completely baffled! Any ideas, anyone?