Can employer Withdraw H1B Extension and re-file for a different client?

USA H1B Visa
1

H1 Extension was filed prior to the H1B petition’s validity end date.

The current project is ending soon. Can the H1B sponsor withdraw and refile H1B extension with LCA for new project location if the original H1B petition is no longer valid?

2

Based on the original H1 extension receipt can the same company file a new H1 if the I797/I94 are no longer valid??

Can anyone please suggest?