Yes, if it is not accompanied by an IDP, and even then it is only valid for 90 days.
Before getting my Thai licence I drove for many years on my UK licence + IDP. The police would quite happily accept it without question and no fines. Fortunately I did not have an accident as it is unlikely the insurance company would have accepted them.
It's not the police that are the problem, it's the insurance company if you have an accident, they might assess you as driving without a valid licence and refuse to pay out.
That is why you see so many Go Fundme appeals for tourists who can't pay their hospital bills after a vine accident.
It's not tricky at all, it's easy. My bank asks the transit bank for the transfer details, they send them over, I go and collect and then show immigration
I am in a similar situation, one of my pensions is paid into Citibank in BKK and then transferred to my SCB account. SCB contact Citibank for me and get statements for immigration showing the payments as international. I think it takes them about 3 working days to arrange.
They have been accepted in CW, BKK and in my current office in Kanchanaburi
I don't use an agent, I do it all myself. If you have the money coming in each month why throw it away on an agent?
I used CW for many years to extend my visa up until 2 years ago and always showed a 3 month contract, mind you, the address didn't change from one year to the next.
I got the owner to do a new TM30 before each visit and he always asked me to sign a new contract, but it was never for a year.
Things might have changed since I moved out of BKK though