Company change when H4/I-539 extension is in progress

I work for employer A who has applied H1B extension for me & it got approved. However, for my spouse, the extension is in process (might taken another 6 months). Now I got an offer from company B & they are saying that they would not be able to file transfer for my spouse. They are suggesting that for now they would go ahead with my transfer (and I file for my spouse later). Is there a possibility that my current employer A can revoke I539 petition application?Kindly request you to advise.