Okay, so I tried it twice.
First time,with an Olight 16340 protected. The protection kicked in after an hour on high and the light shut off obviously.
The second time I used a CR123A primary cell, on high mode. After about 2 hours, the light went down on low mode. I then shut it OFF but couldn’t light it ON again.

I’ll try with an unprotected 16340 but I think it will discharge it quite low