A change of plan can be an upgrade or downgrade to your current ADSL2+ with Home Phone Bundle plan or TPG NBN Bundle Plan.
Simply follow the steps below:
It may take 1-3 working days for change of plan to be in effect. You can also visit this link, which contains information about ADSL2+ with Home Phone Bundle Change of Plan
If you're on TPG NBN, we have created this article that may guide you on choosing the best TPG NBN Plan.
Here's an article as well that may help you on Changing NBN Plans through My Account
If you're not familiar on how to use the TPG My Account, this article is for you: Using TPG My Account & Online Account Info
Let us know if we can be of further assistance.