h1b-approved-for-3months-under-consular-processing

[ParthaT]

Hi, I got my H1-B approved for 3 months but got to know only now with hardly 40 days left and this is under Consular processing. I’m currently in USA under STEM-OPT valid until July 2020. My I94 still shows my status as F1 and end date as D/S. Below are my questions-

1. Can I file for H1-B extension(and Change of status if possible) without going for Visa stamping in India?
2. If I’ve to go for a Visa Stamping in India, what are my odds of approval and re-entry into US? I hardly have 40 days left.
3. If I had my Visa stamped but denied entry into US, what are options? Can I still file for extension under consular and go for stamping again?
4. I’ll not do this but just asking… To avoid Visa Stamping and re-entry issues, Should I simply continue on OPT and file a new H1 again in April 2020?

Any help is much appreciated.