L1 Ext, H1 in RFE Response review

USA H1B Visa
1

Applied for L1B ext, which is in RFE status, sent response on sept 20,

Applied for H1 which is in RFE Response Reciew since Sept 18.

  1. Can I stay, if L1 ext rejects after Oct 1 and H1 status is still in RFE Response Reciew ?

  2. My H1 emplyoer says I can stay but can not work till approval of H1.

  3. If L1 extension approves and H1 also get approved, is it necessary to switch employment with H1 employer ? how much (max) time I have to switch my employment ?

Thanks !