The package starts the day it is added @Leonid , if you added the package the day you left the UK, it should have been activated and ready to use when you reached your holiday destination.
If the package has been added, you should be able to see the package from the Application. If it has not been added and you have been charged you can contact Vodafone from abroad on +44 7836 191 191 free from a Vodafone mobile.
