Do I need to cancel my Non O visa before applying for the DTV visa after divorce in Thailand?

I am on O for retirement and talked to a few agents about this yesterday. The best info came from a Thai agent who said go out and get the DTV and when come back in state yiu are entering on the DTV. The proviso was go to an Embassy known for issuing DTV to those currently on a visa ie Vientiane.

I had a different type of multi entry non-O that I didn't want to lose in case my DTV was rejected and for irredeemable reasons (ie no point reapplying). So I left the country to apply and returned on my non-O once the DTV was approved. The immigration officer noted I had a DTV upon return and asked me to explain, I said I was going to cancel the non-O and then travel to activate the DTV. She stamped me through. I did refer to my non-O status and reasons for switching in my DTV application cover letter, as I felt it was important not to be seen to hide what I was doing. That's my experience.

As long as you don't have a re-entry permit the Non O visa extension will be cancelled the moment you stamp out of Thailand

When does the divorce become FINAL?

Has it been filed already with the Court?

What's your current ending date of your Non O extension of stay as Married to Thai?