So my greatest fear has been realised - the filler has shrunk on every joint
I saw it starting which is one reason I left it alone for a few days. Despite using the best practice I know, very thin layers built up with at least a day to dry, much more in some cases, it's still happened. That'll teach me for trying to do this during lockdown when I don't have access to more suitable products.
Very hard to photograph, but it stands out like a sore thumb in person. A real blow if I'm honest.
Door handle & seam between the windows
Fuel flap
Recess for VW emblem
Where the rear corner was grafted in
Rear corner again, and where the second barn door was used to make the side panel
I'll give it a light sand, which will open up the surface and help it on it's way, then after several days I'll try and fix it by gradually applying localised layers of clear, letting them sink, sanding back, applying more etc. etc.
Maybe see you again next month....