Do all models need to be upgraded at the same time when upgrading the CA GEN product from 8.5 to 8.6?
CA Gen Host Encyclopedia, release 8.6
Please reference this documentation for determining your model upgrade strategy:
https://techdocs.broadcom.com/us/en/ca-mainframe-software/devops/ca-gen/8-6/installing/upgrading-to-a-new-release.html
If installing a new CA GEN 8.6 Host Encyclopedia and still having your 8.5 HE with the 8.5 models, then you will need to move these models to the new 8.6 Host Encyclopedia as the 8.6 Host Encyclopedia will not know of the other Host Encyclopedia's models. This can be done, for example, by performing a download with upload option from the 8.5 HE for each model, and then upload these models to the 8.6 HE.
If you upgrade your CA GEN 8.6 in place and therefore use the same HE as release 8.5, there is no need to upgrade your models as they continue to reside in the same HE as previously under release 8.5.