You could look at contracting to get your maint experience after your Apprenticship. Dont knock your manufacturing apprenticeship, you get to see a lot of the processes airline apprentices only see in textbooks plust the best sheeties I have ever worked with are all ex BAE etc and I am from an airline background.
Try BA Glasgow or Cardiff, may not be the best places managment wise(where is these days) but you will get your exp and maybe a couple of type rateings. I think Ryan air may have a hangar in Prestwick now as well.
Make sure you get the B1 though if you leave Airbus