I think there is a simpler explanation to all of it. He has been forever stuck listening to the same musical instrument day and night, and as the flying reindeer entered the scene, his dreams started to change. It was a culmination of events that changed the way he felt and broke his peace. He might have simply gone soul searching, by himself in plain solitude away from the changes and figured out how to go back to his peaceful slumber. That could explain why he has changed location - to peacefully continue his dreaming journey.
Hmmm, love this explanation 😍 🎶
I hope I will play well next Friday so he can enjoy that peace with the sound of the piano. Though I should somehow bribe him back to my Sunday place 😂