**Q:** Can editors move a journal to a different publisher?      
**A:** Only if they represent the owner of the journal (a foundation or university). If the publisher owns the journal it is unlikely they will agree to a move, which will not prevent a fresh start under a (slightly) different name.

A few case studies are discussed in <A HREF="https://www.ams.org/notices/201206/rtx120600841p.pdf">the 2012 Notices of the AMS.</A>

 - Compositio Mathematica was published by Kluwer, but owned by a
   separate foundation, which chose to move to Cambridge UP.
 - Topology is owned by Elsevier, so it had to change name becoming Journal of Topology, when the editorial board chose to move to Oxford UP.
 - Mathematika is owned by University College London, which moved to Cambridge UP with help of the London Mathematical Society.