H-1B Visa Transfer Question Urgent - Please Help

[Hello1234]

Hello Everyone. I'm transferring my h-1b visa from one desi employer to another desi employer. Basically i'm transferring on the same job at the clients place. I got the receipt notice for my new h-1 petition and the start date for that is 22nd of this month. I asked my vendor to say that this Friday is going to be my last day at my client's location, so the transition will be smooth,instead they were asking me to send an email to my current employer saying that i'm leaving the current position and asked me to continue working for new employer from 22nd. The problem here is, when the H-1B petition is under processing with the new employer, if my current employer comes to know that i'm leaving them, they will revoke my visa. The new petition which is under processing, in case encounters an RFE and for some reason if the application is denied,that will be a big mess. what will be the ideal way of leaving the old employer with the same job at the client location and start working with your new employer. Also once your employer revokes your visa and your new petition is also denied, can we get back to the old employer and is there any way old employer can pull back the visa that has been revoked. Please answer folks at your earliest convenience.Thanks.