My tablet is running Android 5.0 and there are no further updates available from the manufacturer. I cannot get as far as trying to reinstall the Virgin app because it's not it listed as compatible with my device. On consulting the app's documentation, it states that it now needs Android 5.1 or later.
I feel that if an app upgrade is going to increase the minimum SDK required to run, thereby cutting out a significant proportion of the existing customer base, then the supplier should make the old one available somewhere for those customers whose devices don't meet the minimum spec for the new.
As it happens, I managed to find older versions of both Virgin apps on a site called apkpure. I have installed these and they are working fine. At least someone is looking out for legacy device users even if Virgin aren't.