Right. So. Update.
Work messed up my pay and they've been pretty sh*t at addressing their mistake. Sorry, can't give details on this because I have live ops going on regarding this;)
What I can say is that I have crafted what I consider a pretty genius reply to their latest email around why they haven't paid me what I was supposed to be paid.
Honestly, it's like, slightly snarky but with a veneer of plausible deniability that invites a legally culpable response.
Now, while this dispute is going on, my employers have advertised a position is the equivalent to what I'm already doing, but with more contracted hours. Hours that I've been asked to cover, which I think is proof that I'm considered qualified for the post already...