@Bert **********
they wanted a letter from a company signed by an authorized person confirming ongoing employment-- so I wrote myself a letter, since I'm self-employed... apparently that's acceptable. I'd already submitted a legal work contract I'd signed with an agency, but they wanted this as well.
They also wanted bank statements showing a closing balance of £11k. Again, I'd already submitted screenshots and highlighted the last year's worth of invoices being paid to my account, as well as my stocks & shares ISA, but they wanted actual statements with my name & address on it (my RBS digital banking doesn't have it on so had to actually go to the bank and get paper copies and then scan them).