With CS in the cloud' I have to upgrade because that's what Adobe wants.
Not that I'm a supporter of Adobe's cloud strategy, but as of the past 6 month or so you have a choice between using the current version and the previous version. We'll see when the next version comes out if they'll only support two versions or if they'll let you chose any previous cloud supported version.
There are people still running PS6 because it suits their needs. That can't happen in the cloud. Well, it can, but Adobe is unlikely to enable this to happen.
Not that I'm a supporter of Adobe's cloud strategy, but as of the past 6 month or so you have a choice between using the current version and the previous version. We'll see when the next version comes out if they'll only support two versions or if they'll let you chose any previous cloud supported version.