I don't know about you guys, but on my 950XL the 'preparing for installation' or so, as well as the restart, as well as the 'Migrating your data' are all taking forever. I'm thinking easily 45min since completing the download, and still going.
Edit: ... and about fifteen apps now shows as 'pending' in the apps list. Huh?
Edit 2: weird, it looks like these are all apps I installed in the past few (two?) weeks. They now list as 'new'