Situation => 1) Appvd 140 from curr Emp 2) still in 6th yr of H1B 3) 3 year extn not filed by curr emp 4) new employer want to file for 3 year H1-B extension using the approved 140 of current employer

Questions 1) What documents are needed? => 140-receipt, LC Case#. What happens if,
1.1) don't have any info about approved 140 (No Receipt#)
1.2) What is I only have 140-receipt#, but don't have the copy

2) If after 3 year H1-B extension approval by new employer and already started working for new employer, old employer revokes 140, then
2.1) will the 3 year H1-B extension still be valid
2.2) If the 3 year H1-B extension is still valid, and the new employer files for LC/140 after some time, will I be able to port the PD from revoked (approved) 140 of old employer.