I think the current timing for my current pups is going to be something like --

★ Peter meets Peter
★ Possibly something with Thor and Quill? Not sure where Anna landed on this
★ Infinity War Funtimes (Peter, Loki, Rocket, Tony, et. al)
★ Thor hangs out in the past with Frigga so he can see how big of a fuckup Odin was

If Loki wanted to join on the journey, he could. Otherwise Loki could just discover his brother is MIA.

(By the way if you did want to do a Rocket blowup on Thor post-Groot, we could make that happen, too.)