Ahhh I have some Shimano G01S pads but they're too wide and thin. I have some other Shimano pads that don't fit either.
I forget that the G01S pads in the BR615s are a bit oddball.
The lbs just unhelpfully shrugged his shoulders and said there are loads of pads and wanted a code to order them.
Somehow I've ended up with 6 pad types over 4 bikes.