Hi @DarrylTonkin
This is a community forum, know one here can stop Telstra from changing your plan.
The Reason why Telstra is changing it's plans/data allowance, is listed bellow.
https://exchange.telstra.com.au/5g-mobile-plans/
I don't work for Telstra, Never have, I am just a Telstra customer like you.
So the advice I give is my own, In my own time, Guided by my own experience/knowledge.
Which I am always happy to be corrected on.
Rohan
Hello