Since you’re trying to use what’s left over in a topical anyway, I don’t see why it’s important to get full extraction in the vaporizer. I’d just use it until it seems about done to you.
If you’re on a tight budget and you need to get as much as possible out in vapor form though, you might want to try letting it go until the vapor production drops off a lot or you get a “burnt popcorn” taste (that’s how a lot of people describe it).
Trying to go a little longer than you have been might help you figure out whether you’re getting everything you can out of it, but it does increase your chances of combusting with some vapes at higher temps. I’m not sure how easy it is to combust with the Pax, but the Pax thread should talk about it if it happens often.
If you want a guess at whether or not you could get more vapor out of that, if I use a convection vaporizer it generally comes out darker than that appears to be, and I would expect the Pax to be similar, so I’d guess you could try pushing a bit past where you’re stopping if you wanted to.