Valheru_84 said:
…
To me it is pretty clear a not insignificant time has passed between TESB and ROTJ just based on Luke alone. I can’t remember but is it even known to any of the rebel characters where Han has been taken? I can’t recall a time in TESB where any of them would learn about this, so on top of the rebel forces needing to regroup and get themselves in order again after the evacuation from Hoth, the gang also had to try and find out which system, planet and group had Han after probably initially presuming the Empire to have him.
…

The last scene of ESB:

LUKE
(into comlink)
I’ll meet you at the rendezvous
point on… Tatooine.

Other than that, I agree that a decent amount of time has passed between the two films. Luke is very different.