I tried again and Coracle now generated the kind:10063, but it didn't push it to all my write relays, chronicle.dtonon.com in particular.
I found that chronicle didn't have the read and write flags in Coracle, only the DM one (weird, I didn't update my 10002 in a long time).
So I enabled them in Coracle, but inspecting the sent event, I can see that it added the "read" flag (should be empty).
I deactivated/activated the write/read flags again to force an update, that was correct. Then I updated again the Blossom list, that was now pushed to all my write relays.