Is the 15-day consideration period for visa extensions a common practice in Thailand or specific to Pai?

Does anyone have any news of whether covid pass is going to be extended again?

Since you come of a tourist extension you will be stamped from day of application. That is same everywhere.

Not all IO give 15 days under consideration. But many do ATM. Koh Phangan/Samui does not

It's amazing how if you pay 3000 baht instead of 1900 they "expedite" those 15 days lol....

Will they hold your passport for those 15 days?

Highly annoying, yes I know. But applied like this in many Immigration Offices, unfortunately. The FIRST covid extension starts the day you apply for it. Subsequent ones would then however be accumulated / added to the end date of the former one. That "under consideration" practice is the worst, as it makes one so inflexible to travel on. Nothing you can do about it. But you do have plenty time left, so you could shop around for more favorable Immigration Offices that at least not do that "under consideration" crap. One question: You did say your "visa ends". As in you are on your original entry stamp and did not have one regular extension, yet? Most Immigration Offices will then first force you to get a 30 day regular extension (at the same price of 1,900 baht), before taking you application for a COVID extension. That is the 3rd annoying thing.

>Is it the same everywhere

It's same at most immigration office. It depends on the immigration office's workload