Cannot install or see some versions of packages

I am trying to update an AR project to the latest Unity version and am using the arfoundation-samples as a reference. This project is working fine when updated to 2019.2.11. It has ARFoundation preview.4 - 3.0.0 in the project but when I try and install this in my actual project (same machine before you accuse network issues) it doesn't even show that version. The closest is preview.1 - 3.0.0 but when I select it the info panel and buttons grey out preventing me from updating (console says Error fetching latest package info for com.unity.xr.arfoundation@3.0.0-preview.1). Also with ARCore I am on 2.0.2, but this time if I pick 2.1.1, which is the highest that isn't greyed out, I get a red box error saying Unable to add package (Console: Cannot perform upm operation: Unable to add package [com.unity.xr.arcore@2.1.1]) How can one project have these added but not another? I'm now really stuck with my upgrade (from Unity 2018.4.2 if this is useful) so any help is greatly appreciated.