As another option, which does have a cost associated with it, you can continue to have/use your existing Bigpond email address.
When you cancel you can request your email address remain active on the Paid Email product.
https://www.telstra.com.au/content/dam/tcom/personal/help/pdf/cis-personal/broadband/personal-critical-information-summary-paid-email.pdf
When you cancel you can request your email address remain active on the Paid Email product.
https://www.telstra.com.au/content/dam/tcom/personal/help/pdf/cis-personal/broadband/personal-critical-information-summary-paid-email.pdf