G availability for LAX and SFO

There seems to be nothing at all for Sep, Oct or Nov at the moment.

I know this question is a bit of a "how long is a piece of string" but is it likely more will be released over the next few months or nearer the time?

Yes, they come and go at random. You just have to keep checking and be ready to pounce if and when they appear as they're two of the most wanted routes for Gs.