First, the new building.

If you haven't visited recently, you will find that there is now an air conditioned building where the tents in the parking area used to be - on the right side as you enter from Soi 5. The first door has a sign to start here for queue number - thus no waiting in line at the door into the main building. Further down is another door with signs for 90 day reporting, Retirement, and TM.30 reporting. The only drawback is there is no handicap entry for those of us that may be mobility impaired. I was using my rollator (wheeled walker) and had to lift it up over the step to enter.
I arrived at 8:45am and used the first door as there was no line. I told them I was there for "retirement" and showed I had my packet of documents. I was given my queue ticket for Desk 8 (#7 for the day) and told to go direct to that desk in the main building.
Note: They still require you to wear a mask.
At Desk 8, I had to wait as they were processing #5, so 2 people ahead of me in the queue. When my turn came, the Immigration Officer went through the packet with no issues. I then signed two documents as in the past (acknowledgements of overstay penalties and need to report any change in circumstance upon which the extension was granted) and paid the 1,900 baht fee. The only change was they gave me back my photograph and took one of their own using a mobile phone. Then the usual claim check with instructions to return after 2pm the following day. I was on my way home by 9:10am - so total time of 25 minutes. I did pick up my passport with my new extension stamp just after 2pm Wednesday - go to Desk 8 in the main building, no need to queue, present the claim ticket, and pick up your passport.
I use the 65k per month method - ordering my bank statements for the past 12 months at Bangkok Bank customer service at Tesco-Lotus South a week ago Monday as they need about 5 business days to get it from Bangkok HQ - fee 200 baht. On Monday this week, I returned and had them prepare my two bank letters for Immigration - the one verifying the account (required whether using 800k in bank or monthly income method) and the other listing all my foreign deposits shown on the statements (required for 65k per month method if you don't have an Embassy verification letter which is not available for holders of USA, UK, or Australian passports). Pattaya Immigration wants the letter showing deposits rather than the bank statements as proof you deposited at least 65k into your Thai bank account for each of the preceding 12 months.
I used the checklist provided by the Pattaya City Expats Club on their website at: https://pcec.club/CHECKLISTS-Extensions-of-Stay. The checklist notes to do a transaction and then update your bank passbook on the day of application. I omitted this step and nothing was said about needing it.