Current Amendment on H1b Got Declined and H1b Transfer is in Progress - Please Advice

Hi,

I have valid H1B Visa and I-94 till July 2018. I am with employer ABC(which is a consultancy). My petition which is valid till July 2018 is for Texas (for EFG client). Now last year I moved to Newyork and my employer filed an amendment for new client and location change. I had received an RFE for this amendment 3 months back. This week they declined the RFE. Mean while last month I got an offer for XYZ company. They have filled the LCA, and are planning to file my petition in premium next week.

Now my questions are:

1) What is the legal buffer time people are having to leave USA when their amendment petition is declined?
2) As I have valid petition for Texas till July 2018, can I work in that location?
3) Can I stay in USA after putting a resignation to my employer ABC and wait till XYZ company's approved petition? Is it legal that way?
4) If Point # 3 is valid, after getting approved petition from XYZ company, Do I have to leave USA and come back to maintain my status (May be have I94 refresh, etc), or I can just start working for XYZ company.
5) What other options do I have?

Please advice.

Thanks,

Current Amendment on H1b Got Declined and H1b Transfer is in Progress - Please Advice