H-1B extension with an approved 140 from previous employer

[skd1900]

Hi all,

To be eligible for further H-1B extension, will my current employer have to file for PERM LCA 1 year before the actual 6 year period of H-1B or 1 year before the H-1B expires (considering that i got H-1B valid beyond the 6th year because of 140 approval through previous employer) ?

Thanks a lot in advance,

Regards,
SKD