ascendant

So... Pattaya Immigration was a nightmare, arrived at 8:30 AM and left at 3:30 PM... and when I returned to pick up my passport, I saw I had the "under consideration" and it asked me to come back in 21 days on February 11. I'll be in Bangkok, but I guess I need to plan a little excursion back to Pattaya. Should I be prepared for another all-day affair for this return? Is it going to be like last time where I have to go in on a Friday and then they don't return the passport until Monday? Do I have to do anything / prepare anything, or do I just bring myself and my passport?

I tried to get my first COVID extension- I was surprised when they wanted me to come back in 15 days while it was "under consideration." Since I was going to be relocating to a different city to get it done. I have some questions about it. When they say "come back in 15 days" does that mean 15 days exactly (assuming that immigration is open on that date?) Or does it mean some kind of window? e.g. Come back anytime within 7-15 days? Do all regions have this same "come back after 15 days" rule? Any suggestion of which immigration office is the "best" (easiest, fastest) to get Covid extension in either Bangkok or Pattaya?