It seems our story is quite similar. I also started as a drivers mate when i was 18 for a company called Dunster House and passed my class 2 a month before my 19th. Learnt alot working there, but same as you i wanted to go bigger and better and eventually into Europe. The best advice i can give you is to keep any eye out for any european transport companies near you and just phone them and explain your situation. Ive done work both on Class 2 & 1 for two different companies going over to the mainland and after telling them im only 21 they were actually quite keen to get me onboard, because it means they can teach you there way of doing things and potentially they have someone who can offer more years of service than a guy whos 60 and going to retire in a couple of years time. You might get turned away from a couple of places but someone out there will give you a chance, you’ve just got to be keen and willing to learn, and when you finally get let loose over the otherside you’ll absolutely love it.