The ring sizing has been such a debacle, first with needing to buy (!) their special ring sizing kit because standard sizing wouldn’t be accurate they said, and now they say that the ring sizing kits weren’t true to size and suggest this:
When in doubt, order a larger size. You can always adjust a larger Index 01 to feel smaller with a foam adhesive or clip but you can’t make it larger!
Size up and shim it with foam!