RFE on 485 for birth certificate

[Talk2sood]

I have applied 130 for my parents and concurrently my parents applied for 485, 131 and 765. We did not receive 131 approval yet but last week we got an RFE for 485 (for Parents birth certificate due in 87 days). 

Questions are - 
1. Can they leave US to arrange their birth certificates (or NABC and affidavits from relatives) without abandoning their application? 
2. Should they wait for 131 approval before traveling? Is it even going to get approved or everything will remain on hold due to the RFE for 485 (mentioned above)? 
3. Given they are born before 1969, will USCIS accept NABC received from the Indian consulate? I will attach their School and marriage certificate as a secondary proof of their birth. Will that be sufficient to reply back to USCIS on RFE? 

Many thanks in advance- 

Regards, 
Sandeep

[pontevecchio]

1. They can get appropriate affidavits from family "elders" while they are still here. What is their present status?

2. The RFE needs to be responded to. They do mention alternates. One of the important ones is NABC from the city/district of birth from the Registrar of Births and Deaths in that area. You can do more with honey in this case than with vinegar. Absolutely doable and in many cases routine . The Embassy one will not do.

3. See 2.