eb2 eb3 downgrade, AOS pending, travel, change address

[OneHB]

Inputs appreciated !

My Scenario
1) H1b visa (sticker in passport) expired in May 2017
2) Current H1b valid for next 3 years
3) eb2 - PD - 2014
4) Oct 2020 - downgrade to eb3
5) EAD / Combo card - received last week - Feb 2022
6) 485 - pending
7) eb3 - 140 - pending

Q - Is this valid, travel to home country - india
    1) Attend H1B interveiw - get the stamp in passport
    2) Return to US on H1b

Q - current residence - state A - close out apartment lease
    plans to go india and after returning reside in state B

            Can I move to state B, update my address and then travel outside usa
            Can I change address while I am in india

Q - pandemic, delay in visa interview appointments, number of days I can stay in india ?
    planning trip for 1month +