Stop Invisalign Early? Waiting for Trays But Doc Says It's For Spacing?

My dentist mentioned to me that she lost two of my trays, which are being re-ordered. After these two, I have three left before I finish my full set! She said that, on her software, these three are indicated as "brown" (versus "blue") and are only necessary if there's further spacing issues. Just wanted to fact-check this and make sure that I'm getting all the trays I need. My teeth seem decently straight, but I got Invisalign for my bite. Should I ask her for those trays? Thanks!