Can I border bounce my Non-Immigrant O visa for 90 days before March 17?

To make the most of this visa:

1. Bounce out on March 17, 2020. You'll get stamped for another 89 days.

2. Bounce out again on March 27, 2020. You'll get stamped for another 89 days. Your "depart by" stamp should be June 24.

3. Extend your entry stamp for 60 days at your local immigration office for visiting Thai family for 1,900 THB. You'll be able to stay until August 22, if my math is correct.

Hope - you should get 90 as multiple Non Imm

But hope you'll get a more definite answer from a more in the know member

You'd get 90 days, since it's a no-O mulitple entry visa.

@Robert ******

...will he get 90 days with this one year Non O ...which I assume is for Marriage to Thai obtained at Savannakhet?

As long as he bounces out and back by March 17th...

90 days from date of entry.