macOS Server Upgrade
I'm migrating a Mac mini (mid-2010) running OS X 10.11.6 with Server 5.2 to a Mac mini (late-2014) running macOS 10.14.6.
Migration Assistant went fine but on the 10.14.6 mini when I find the Server app in the App Store it only offers me Server 5.9 which of course requires macOS 10.15. How do I install Server 5.8 (or whatever the 10.14 compatible version is)? It used to be that you could click on whatever the latest Server version was in the store and it would automatically download an earlier, compatible, version if required, but that doesn't seem to happen any more. Now the "Upgrade" button is greyed out and I can't find any way to install an earlier Server app version.
Mac mini 2018 or later