I94 dates changed due to new H1B amendment overriding H1B extension

[Jai05]

I have a unique case, I am primary alien working on H1-B. My company has applied H1-B amendment in normal processing and in the mean time applied H1B extension with premium and I got my I-797 A approved for 3 years.. While applying my extension we also applied H4 extension for my wife & 2nd daughter. Now, H1B amendment got approved with previous validity and attorney told that latest I-797A becomes active. Company is applying the H1B extension again, but not sure if they can do it before the I-94 expiry date
Here is the sequence of things happened:
1) Earlier, I had the H1B Visa valid till 11/22/2019 and H1-B amendment was applied in normal processing in May, 2019.
2) With I-140 approved, Filed H1B extension in premium processing on 09/05/2019 and also applied for my dependents H4 extension 
2) Primary Applicant H1B petition got approved on 09/18/2019 with end date validity till 09/02/2022 and I-94 validity till 09/12/2022
3) H4 extension is still in Processing STATUS with fingerprint completed.
4) Primary Applicant's H1B amendment with normal processing got approved with previous validity of 11/22/2019 and I-94 validity till 12/02/2019
5) Company is applying the H1B extension again. They are trying to repost LCA on 11/22/2019 which will take 7-10 working days.I am requesting them to use the existing LCA from my previous extension and file the H1B extension to file it before 12/02 to keep my lawful presence active  
6) If company attorney uses the existing LCA, they might file the H1B extension by 12/02

Questions:  

1) Is Fedex confirmation no. fine or do we need to get the Receipt no. before I-94 expires for lawful status
2) I should plan to go abroad and come back with new visa stamping within 6 months, even if immigration team files it before I-94 expiry date, as he got delayed to file before I-797A end date. Please let me know more details on the re-entering within 6 months for getting new  I-94
3) Dependent- I-94 was valid till 11/22; but H4 extension is in progress with fingerprint completed. Does it takes my H1B amendment's I-94 of 12/02 for them as well.
4) I can enable back Prev approved H1B extension by Using the same for Visa stamping and re-enter to US. Is it correct?

Appreciate if you can help with your suggestions/thoughts.

Thank you.

Edited November 26, 2019 by Jai05