Hey @AnnMarieAustin , Welcome to the 3Community 🙂
If you change the scheduled top up your plan won't automatically change however you won't need to call 1913 to change your price plan.
When you are logged onto My3 you should see the "Your Plan" section and then "Change Plan" is also in this box so you will have the option to change the plan there. I would recommend waiting until your plan has expired or until you are ready to top up again as once you have changed the plan you will have no allowances or active plan until you top up to activate the plan.
