F2 RFE while H1B->F2->H1B application

[vivs33]

Hi,

My H1B max-out in July’2018 and I moved to F2 because my PERM was not approved when my H1B got maxed-out. Now, In Oct-2018 my I-140 got approved and I applied for my H1B extension in regular processing in Dec’2018 because premium processing was suspended till 18thFeb’2019. Now, in March’2019, my H1B extension got approved for one year and I started working again. During July’2018 to Feb’2019, I was on F2 receipt and it remained pending even after my H1B got approved. I didn’t withdraw my F2 application because i was under the fear that my stay will be consider illegal if I withdraw it.

Now, suddenly I have received an RFE for my H1B->F2 application(which I applied in July’2018) even through my F2->H1B(which I applied in Dec’2018 based on F2 receipt) application is approved.

RFE is for following.
A. Maintenance of F1 Status
Prove my spouse -F1 holder was maintaining F1 status when I filed for F2 application by providing any of the following documents

1. Provide all I-20
2. Letter from school that F1 holder is attending classes
3. F1 holder’s OPT EAD
4. If on CPT/OPT, provide three most recent pay stubs

B. Residence abroad
Provide evidence to establish that you currently have a foreign residence.
Please note that I don’t have any residence in my home country on my name.

Now, I have following query,

1. My F2 to H1B was approved based on F2 receipt number then why USCIS is asking for evidence for my old H1B->F2 application ?
2. Can I withdraw H1B->F2 application after receiving RFE ?
3. If I withdraw my application then will my stay(July’2018 to Feb’2019) consider illegal ?
4. What will happen if I reply to RFE ?
5. Does it matter now, if USCIS denies or approves my H1B->F2 application ? 
6. Can I request USCIS to approve my F2 till my H1B start date ? 
7. Will this RFE cause any issues in my future H1B extension application/H1B VISA interview  ?

Thanks,
Vivs