The blue tree management office on the floor below the immigration office at Blue Tree can also assist with photos and photocopies and so on if needed.
For the covid one I would do it a day or so before March 25 as all offices will be busy on March 25. Also, not all offices start the covid extension from the date of approval. Phuket offices for example start from the date of expiry of existing visa/visa exemption (or extension thereto). (note: some commentators here will say that if it is your first covid extension it always will start from the date of approval, but this now not common - it normally runs from the date of expiry of your current status, as it did for me and many others I know in Phuket recently) So, if so, theoretically you could be approved to stay until early June following that procedure.
any day within the 2nd month would prolly be ok. They will only tell you to come back later ( if very early) if they are busy. And blue tree office is rarely busy
you can have your documents copied and photo taken at the blue tree management office on the floor below if necessary. They are very helpful and know what you need
you need a form tm7. A copy of your passport info page and a copy of your visa and 60 days passport stamp for those 60 days. Also a copy of your departure card (tm6) and a recent photo and B 1900. Sign all copies and put your phone number and email address under your photo at the back page of the tm 7
If you are anywhere near blue tree waterpark then do it at the immigration sub office there as it’s friendly and quiet