I think either Filoni or Favreau has been quoted as saying it's scripted already...
Felt like a proper conclusion to the arc and sets up a lot of interesting storytelling ground - multiple cloning projects and the Imperial Remnant still kicking, a resurgent Mandalore (potentially very interesting for the post-sequel period, with the Republic either in disarray or collapsed).
Yarp, and rumoured to be that the slated Filoni movie may well bring together Mando, Ashoka and Fett. The suggestion is that it may be a juncture where some continue on from and not others. I can see Ashoka and Grogu continuing on with Fett and Mando ending their stories perhaps? Especially as there are now these "grey" force users that operate for good outside of the now defunct Jedi.
Also, a friend pointed something out to me about the last episode, not going to say anything just yet, don't want to spoil anything for those that haven't watched it.