You will have to go into Asq quarantine. You will need a COE, which requires copy of passport,visa and re entry permit, Hotel booking, Covid insurance for the time you get stamped back in for, PCR test before flying, T8.
Bangkok would use the same or very similar rules to Phuket , testing, approved transport from BKK, SHA+ hotels. It wont be a free for all, a long way from that.
Target date on Bangkok sandbox is always moving to a future date at present. Last sniff of information available said November 1 if they get 70% vaccinated in time. Should be by Christmas 😂