Filling H1b transfer after l-94 expiry - is it allowed?

I am on H1B Visa in USA and need some inputs from you related to my query for H1B transfer after I-94. Is expired
My I-94 was expired on 8th Jan ,2020 and my extension was filled in regular mode on 25 Dec2019
I have an offer from new company which is US based (Equifax)
My question is - is it allowed to file H1B transfer after i-94 expiry ?
I have approved i-140 and want to know what will happen if my current extension is in progress and new company filled my H1B transfer and I join them on receipt notice as premium processing is stopped now.
Kindly suggest .

Read this as it covers multiple scenarios and risks: