Update after 2.5 months pissing about - they've closed my account, after asking me for all sorts of crap including my self-assessment returns (which I gave them) They didn't outright ask me if I was a sex worker but it's clear they put me in that bracket.

I'll consider opening a few new accounts with different providers, stay below the radar, and have a more well fleshed out cover story next time. (This time I randomly claimed to be doing massage which was probably stupid but they caught me on the back foot.)

Update on this - I finally received my money back today, only after starting the process to take them to the Financial Ombudsman. Just 8 months after them freezing my account 🙄

I will not ever use a personal account for business again, but given this experience with Cashplus, I will never recommend their business account as their customer service and communications have been absolutely appalling.