At this time we would fly in mid-July 2022, book a return in March, 2023 but want to change it to July, 2023
There are two variables at play here if your intention is to change the return - which is the EARLIER OF original flight OR one year from ticket issuance.
Your original flight is March 2023, but your ticket was issued in May 2022. My understanding is you need to contact SQ to change the return leg before March 2023, not May 2023?