Point Henry Corio bay does have a wave generated by passing ships that can be ridden by sup.
Having kiteboarded & sailboarded flat water there for many years its always been a novelty when you see a large fully laden ship who's skipper is in a hurry...
Being on a fast moving kite board you can line yourself up in the safe shallows of the point to the general area the wave will break, there is no need to go anywhere near the ship or shipping channel as the water is too deep for a ridable wave anyway.
Obviously the waves shape is governed by ships displacement speed, tide & direction of travel, in or out of port, at times it can often be more like a mini tsunami than an ocean swell, as the water tends to drain off the shallow point followed by the ships wake in the form of a wave...or two, about waist high, its not really a nice peeling wave, but rather a foamy closeout.
The wave can be ridden for a few hundred meters at best.
If you want to ride it on a sup.... look up port movements for the day, & observe where the wave is breaking on a ships passing.....go hang around....may be a while though... as traffic in corio bay is nothing like port philip
Just a word of caution....the wave can suck dry....sending you into the mud.....you will be likely to come up with a face full of sea urchins
heheh.....good luck
ps....DJ....here is a good expedition idea for you ....take your gopro & document it for everyone.
you can even make it an interesting trip by taking a short cut getting there by paddling from north side of corio bay at the end of avalon rd
.. and I sure will wearing my booties.. 
