Description of problem:
After downloading packages sucessfully, I reboot with
dnf system-upgrade reboot
The system reboots. A message like 'System is upgrading, this will take a while' appears in the upper left corner. After about one minute, the systems reboots into "normal" Fedora 24.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Start upgrade with sudo dnf upgrade --refresh
2. dnf system-upgrade download --refresh --releasever=25
3. dnf system-upgrade reboot
No installation of F25 packages, instead reboot to F24
Installation of F25 packages should start
Recent update of F24 and new F25 packages two days later solved the problem. Update worked fine.