Now, all courses are B1 and B2.
Contractor job are mainly B1 in the hangar.
B1 with B2 are appeared more in job search.
Avionic will be a history. But many B1 are useless in Wiring Diagram Manual.
More B2 are taking B1 exam to be B1.
Most line defects including APU change are done by line people outside in the open hangar with a few exception if the hangar is available. It costs over three thousands pounds to hire a hangar for a day. Will your boss think you are indispensable to be warm in the hangar.
Line nowadays is is a small kid job with computer literate mind to fix most defects. A380 CBs reset are mainly done using onboard PC. IFE is mainly the cabin defects which is normally fixed by hard reset. Same for most ECAM defects.
hangar experience provides basic in deep training. Line job is challenging and most of the time is to kick the tires.
Avionic???????? wil be only fairy tale soon. It is mainly one man per aircraft on line. Expecting B1 to open a panel for you by dragging him away from his departure aircraft.