We knew that Guardians of the Galaxy Vol. 3 would be a bit of a swan song for the titular team of intergalactic heroes; we even thought it might be a swan song for Rocket Raccoon. What we didn't expect was for it actually to be a swan song for Star-Lord while the Guardians and Rocket carried on without him. And yet, he will return.
That little tag at the end of the movie does reinforce that Chris Pratt will be back in the role at some point, but it's pretty obvious that it won't be in Phase Five. Peter Quill has finally returned to Earth to see his grandfather. It's a full-circle moment for the character that was a long time coming. His journey into space as a Guardian of the Galaxy is over for now. And with James Gunn now setting his sights on the DC Universe, there won't be another installment in the franchise (for now, at least).
The next place we see the Guardians will probably be in an Avengers movie. And yet, we're not entirely sure that Quill be with them at that point. Sure, The Avengers will need all the help they can get in Phase Six when they have their first reunion, but don't be too surprised if we don't see Star-Lord until the final movie in the Multiverse Saga Avengers: Secret Wars.
Heck, with everything up in the air right now with the Guardians franchise and the fates of its characters, we wouldn't be surprised if Star-Lord's return didn't take place until Phase Seven.