Can one update Petitioner info in CGIFEDERAL/DS-160 after making payment but have not scheduled appointment yet?

[wxm]

I filled out my DS-160 and then filled out the forms in CGIFEDERAL portal and made the payment. I have NOT yet booked an appointment. I qualify for visa waiver, so I'm only looking for document drop off appointment.

But since then, I applied for an H1-B Amendment+extension, and received a new receipt number. Once the case is approved, I will receive a new expiry date as well.

Q1: Will I be able to just go back on the CGIFEDERAL form and update the Petitioner information with the new receipt number and expiry date?
Q2: Do I have to fill in a new DS-160 (since I think we fill in the Petitioner information there as well)
Q3: In case I fill in a new DS-160, can I just update the CGIFEDERAL with new DS-160 confirmation number and Petitioner information?
Q4: Is it safer to just start from scratch and make a new payment?