Same as several other people on here I have not been able to watch box sets on TV Go since last Friday, it asks me to upgrade.
I am using a Windows 10 laptop and get the same issue whether I use it thru a browser or thru the app.
I have tried clearing the cache and have uninstalled and re-installed the app but it makes no difference.
I am on the Ultimate Oomph package so box sets are included and I have always been able to watch previously before last Friday.