Hi @Mark.Lancaster and @smbrennan,
Thank you so much for your patience while I got a definitive answer to your questions on accessing different versions /products in the collections with named user access.
Whatever Previous versions you(in-policy plus any grandfathered previous versions) for each product in the Collection may be installed concurrently/simultaneously on up to 3 electronic devices.
The use of the product is limited to sequential use, which means you can be actively accessing and using (interacting with) only one version of one product on one device at a time. Of course you can switch between products as you wish – 20 seconds using AutoCAD on your smart phone, switch to Revit for 30 minutes on your laptop, then switch to AutoCAD on the laptop, etc. What would not be allowed is two products or two versions of the same product being accessed and used (interacted with) simultaneously as this would mean different users are using a single user’s account which would be non-compliant.
It's not whether a product or version is “open” on a device but rather whether it is actually being accessed and used (i.e., actively interacted with) by the user. Concurrent active interaction (access and use) to more than one app at once indicates more than one person (user) is using a single entitlement.
Short version: You can have multiple products with the Collection open, including multiple versions of the same product, as long as you are not actively interacting with them at the same time (which would be impossible since you’re only one person).
Again, my apologies about the wait. I hope this clears things up, and I apologize about the confusing verbiage earlier as well!
Sincerely,
Amanda
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Amanda Pruyn
Principal Community Liaison Manager