I think flame 6 is a bit outdated, so it will be a big leap forward. Of course flame 9 compared to flint 9 would be a bit greater, but it is still a good choice considering the speed advantage against flame 6. The whole thing depends on the structure. If your company buys the linux version you will get good speed results on sparks and other CPU based operations but lack a little on hardware acceleration, if they choose the tezro version you’ll get the opposite (since flint supports only one CPU).
Anyway you will be able to use your existing skills and knowledge without effort. (And maybe will be surprised on how GOOD are the differences in the last versions)