Question about CLP

Hey everyone, so I hold a class A CDL in California. Recently I decided to take work at a place that drives buses, so I needed to get my passenger endorsement. So I have a clp (commercial drivers permit) right now to acquire the passenger Endorsement and am going through the driving training required for that. Anyway, I think I have come to the conclusion I'd much rather drive something other then buses and on top of that this company has been jerking me around delaying my training, and some other things. I've been talking to some other companies.. So I am wondering what would happen if I were to bail on this job and what happens to a clp after it expires. Will it simply go away and my CDL class A stays as it was before I applied for the CLP? Or have I gotten myself in a situation where I have to see this through and complete the passenger endorsement to keep my CDL? Thanks in advance to any who see/reply.