Right so thinking no point bothering with anything else until Physio has looked at me and bike fit.
Went for a ride, unstable as hell, totally miffed.
I then just thought, it feels like my left foot is in a different place over the pedal than my right, however they're exactly the same.
My saddle is at 72.5mm now, the cleats moved as far back as they'll go, surprisingly that didn't feel weird.
Hoiwever I thought, perhaps if there is some something giving the effect of shorter left leg, moving the cleats forward will effectively lower the saddle for the left side.
So I've moved the left side cleat to where I oringnally had it, left the right shoe as is, the left cleat is 6mm further forward than my right.
What I noticed when I did a 37 mile bike ride today is better stability slowing down, better acceleration, no swerving of the bike and smoother pedaling and ability to keep a more consistent power reading rather than it jumping up and down.
It's still far from perfect but it seems better than at any point this year.
I'm not sure if I should move the cleat even further to see if it adds any stability or to add a shim, or just persevere until July 29th as it is.