As you may be already aware, the additional 10 COVID-19 rebatable sessions have finished (as of 31 Dec 2022). This means that clients referred by their GP with a Mental Health Treatment Plan (MHTP) can claim a maximum of 10 sessions through Medicare in 2023. If your last referral letter was for the 10 additional COVID-19 sessions, and you have not utilised all of these items in 2022, you may use this existing referral to continue seeing your psychologist in 2023 for up to six sessions (if you have 6 remaining sessions on the referral) before seeing your GP for a re-referral for the remaining four sessions for that calendar year (allowing for a total of 10 sessions within any calendar year).
You may be able to claim any additional sessions through your private health fund, however you should contact them directly to find out whether your level of cover allows for this.