Umm....flame....
Lots and lots of flame....

Thrips are difficult to eliminate as

A) Eggs are laid in the very youngest growth and flower buds, which are difficult to penetrate w/ spray.

B) Larvae grow and feed between the layers of the leaf- also difficult to spray.

c) Upon emergance from the leaf tissue, immatures drop to the media and puepate there, underground- also difficult to spray.

Takes a systematic response- bombs work well, but you have to re-apply at least once in order to eliminate subterraneans.

Google " thrip reproductive cycle" and you'll find all kinds of info on life cycle/temperature- use this and the average temps of your room to determine the appropriate timing.