SymptomsA customer cannot change the hosting type for a Parallels Plesk Panel (PP) domain if the domain's subscription was created on PP 10.x and 11.x nodes.
PBA-S Customer CP > Websites & Domains > (Select domain.) > (There is no way to change the hosting type for the selected domain.)
CauseThe issue has to do with the "Domain Creation" permission being disabled in the PP Domain Hosting Plan in PBA-S.
The Create_domains permission is intended to be used for resellers (in terms of Parallels Plesk Panel)/ non-auxiliary PP Clients (in terms of PBA-S) only.
It manages whether an account can create subscriptions and primary domains (not aliases or subdomains). It can be managed through the Parallels Plesk Panel GUI on the reseller's permissions tab in the "Advanced" section.
However, this permission also affects the ability to change the hosting type for existing subscriptions in Parallels Plesk Panel.
ResolutionThe issue will be fixed in a future release of Parallels Plesk Panel.
It is recommended that you enable the "Domain Creation" permission in PP domain hosting plans in PBA-S.