You need an active Telstra branded service or a JB Hi-Fi BYO Mobile plan to redeem your Telstra Plus points. If you move your Telstra service to JB Hi-Fi or change your current JB Hi-Fi BYO Mobile plan to an Upfront JB Hi-Fi Mobile plan, and have no other Telstra services on your account, you will not be able to redeem your Telstra Plus points or access the Telstra Plus program.
Your points balance will remain on your account in accordance with the Telstra Plus Terms and Conditions; however, you will need an eligible Telstra service on your account to redeem the points.
For more info see What's not included in JB Hi-Fi Mobile plans.