is the correct response here to upgrade the product first so I can specify it for a remove task?
Paradoxically, that would probably be the easiest approach. The point product installers usually have the ability to handle many more versions of the product than you can hold in the repository, so a two-step approach of "upgrade everything to the latest version" followed by "uninstall the latest version" should cover it.
Gonna add to it that some upgrades of the 8.8 fail due to the mix-in of the W8/2012 version as P3.
So if you had like VSE 8.8 RTW installed you cant upgrade straight forward to P4 without installing P1 first. (and even I have seen that failing a few times).
Now I can imagine that uninstalling will have commonly issues.
Just my addition to the topic... (PS: mostly the Remove task works just fine on VSE P4)
this is the unfortunately the only approach I've found. I'm marking it as the answer but I don't really like having to do this and as @justav mentions it doesn't always work that well.