aptsearch,
I had similar (not exactly like yours) situation few months back.
This is only my thoughts for your situation. "This is not an expert opinion."
Regarding your OPT:
If you want to be on safe side you could extent your OPT. (I believe your H1b will be approved by Feb)
1. Unless you are working for nonprofit company or new Company B, is nonprofit, its not a good idea to withdraw H1-B application since its very hard to pick up on lottery next year again.
2. If I were you I would pick option 2. You don't even need to let your company A know to start H1-B transfer.
3. If you don't hear your result by the mid of January then only its better to apply for OPT extension. USCIS need to receive your extension application before your OPT expires and during that gap period you can still work legally. (ps your application should approved by Feb)

Jai Nepal