Tried to read a ton of threads before asking, but can roaches become immune to Alpine? We have been using it with the occasional mixing with Tekko Pro monthly for about 18 to 20 months now. We saw a huge drop off in roaches, and now all of a sudden we are starting to see either german or oriental roaches again. Someone at domyown said they can become immune to Alpine and that we should rotate with Temprid FX. So is it true? Can they become immune? Is Temprid a good second option? Is it non-repellant? Or what non-repellant should I rotate with to eliminate both german and oriental roaches? Temprid seems to be so expensive too so didn't want to waste money if not needed. Any advice would be greatly appreciated. This is for about 40 apartment units that we help maintain.