Change of client between LCA approval and H1b extension

I have a very unique situation here. Please help me on what I can do.

My visa is expiring in 7 days. When I initiated my H1b extension with my employer I was working for Client C1 in Location L1 and they applied for an LCA accordingly. But since then my client has changed but the location of the new client is 20 miles away from the L1.
Can they file my extension based on the new LCA?
Do the client name and location have to match the current client name an location?

your employer can amend the pending extension with new client/location based LCA.

I have not applied for my H1b extension yet. They will file it in a day or two. The LCA is with old client name and location. Both the old and and new locations are within the same county and MSA.
Can they still file my extension with the LCA I have?
Also my H1b is being filed in premium processing. Should I get it changed to regular for my situation?

Getting a new LCA is pretty straight forward and easy, not too expensive(its all online). Why you guys are trying to add uselses confusion with the previous client’s LCA?
BTW, why YOU ARE worried about the LCA and stuff? Its your employer’s responsibility, he/she will take care of it. Also YOU will never own an LCA OR any part of the H1B petition, your employer only would. So, just relax and let your employer do his job.

I am worried because my visa expires in 4 days.

What are you guys doing just till the last few days to file an extn? I guess if you file with your old LCA, denial is more possible. I have seen getting LCAs in 24 hours too(its online). Not sure if your employer is wise enough to address this much earlier.