It's not terribly unusual for a show to get dropped by a network and picked up by another; some other heavily serialized genre shows that have changed networks include Buffy (started on the WB and moved to UPN), Stargate (started on Showtime and moved to Sci-Fi) and The Expanse (started on Sci-Fi and moved to Prime Video)

Yep, the first four seasons were on a little network called PTEN that had four shows. The fifth was on TNT