I would not even waste your time calling. MPC Manilla are absolutely useless and they have no power to open-up seats for you. If you were Diamond - I might suggest calling a few times to push your case (my partner is Diamond and sometimes it works) but as you are Gold - hold your breath.

For standard award tickets, I know you are allowed to wait list for up to three flights. I am not sure if this is the case for upgrade award tickets, but no harm in calling and finding out. If it is - get on as many wait lists as you can for the flights around your desired time, this will increase your chances.

In terms of auto clear - I always think it works and have never found award availability first (searching on CX) before it was given to me anyway because I was wait listed. If you want - there are some programmes - not sure what they are called KVS Availability? Do a search on here and there are loads of results and the programme will check for availability once a day every day.

In all honesty - just forget about it and if it happens, as midlevels said, you'll get a text or an e-mail.