Good to know you got everything working
I am assuming you have used the RemoveUpdates.exe from the /Base folder. Although that does work its not recommended as you could cause issue with the Binary applied as part of SP16
Otherwise did you uninstall SP16 and re-installed the SP15 package, as that could be the other option.
However in saying that if you did encounter issue in SP16, opening a support Ticket would still be recommended to drill down and figure out the cause