From my experience you need 2 things to pass the ACCA’s, firstly an employer who cares (and backs this up with study leave and other support) and secondly huge self-motivation, if you have both of these then passing the exams is a relatively pain free process, however if you get no study leave or exam leave etc its very hard to be able to find time to juggle everything and the exams will be far harder to pass.
If I was you I would look for a new job & target companies which give good exam leave, the fact you’re currently studying plus you’ve experience behind you should make you quite attractive to potential employers.
Worry about salary when you qualified, right now you should be looking for a package which gives lots of study leave and fees paid etc