Howdy Red
I haven't sailed at Frankston, so I stand to be corrected by a local, but I have sailed in the area. Gnotuk Avenue (Melways J7) at Aspendale is the popular launch site and is only a matter of minutes away from Frankston. I think Frankston itself is partly sheltered by Mt Eliza and Olivers Hill unless it's blowing more westerly when it should work OK. There are some no-sailing zones near the pier that you would need to be aware of. Gnotuk gets cleaner onshore air in the prevailing souwesterlies and there's good parking and grassed rigging, but can get crowded in summer (but what beach doesn't?). Frankston wind reading are usually a bit lower than elsewhere in the bay. See earthsci.unimelb.edu.au/engage/dynamic-earth-updates/bay-winds
Not sure whether it's because of wind shadow generally, or crap positioning where the reading is taken. (City wind reading station is surrounded by buildings).
Hope this helps.
Cheers