It's possible for hybrid environments to support multiple UPNs for their users. The email address of the user who signed up to the Patch My PC Cloud might differ from other users within the organisation who would also want to sign into the same company of Patch My PC Cloud.
At this time it's not possible for Patch My PC to associate multiple domains with a single Patch My PC (cloud) company, nor change the primary domain used to sign up with.
This can be a tricky experience when new users request access to the company but they're using a different email domain. In this situation the administrator of the Patch My PC cloud company does not see the requests.
This feature request is for the ability to manage domain association and add multiple domains.
I had a customer that removed user-based access and switched to EntraID groups split up into all of the supported roles. Customer then lost access to their portal since the initial account used to connect the portal to their intune tenant was the default onmicrosoft account which is associated to their GA and admin accounts. However, they were using the primary domain account in the entraID group access management groups which the portal was unable to verify since it's doesn't match the onmicrosoft domain that was used to register the tenant.
Customer then added in the onmicorosft accounts to the entraID group and was able to successfully login. However, the portal should be able to identify both of those domains since ever tenant has the onmicrosoft account as default anyway. This would prevent loss of access in these situations and less confusion when provisioning new accounts.