What happens to the electrons of semiconductors?
Individual electrons move around in semi-random ways, with a bias of moving along the E field lines from negative to positive. "Current" is only predictable because many many electrons are involved, and in the aggregate, their random behavior largely averages out and we are left with just the E field effects on the herd.  

From this view it should be clear that individual electrons can end up lots of different places after a certain amount of charge goes by. For a sustained current such as you describe, many electrons are moving all along the closed conduction path. Some may indeed swap positions after some amount of charge has flowed.  

None of this has anything to do with semiconductors. The same thing applies to electrons in a resistor or a copper wire.