Moves afoot already.

https://www.autosport.com/motogp/news/134011/petrucci-and-pramac-to-split-after-2018-season

Season not started and already spaces becoming available and spaces that aren't available being talked about getting filled.
Interesting to see the talk of a factory Duke seat. A few ifs and buts for that to happen I'd imagine.

And some folk definitely not moving
MotoGP?
As it says, 2 more years for Vinales at Yamaha.