For Info: redefined Substitution not immediately available

I created a substitution so I could type character initials and get the full name.

After adding the substitution and using it, I realised I had forgotten accents; I edited the replacement & said OK, but the revised substitution was not available until I had quit and restarted Scrivener 3 (Windows)

Now I am not so sure whether it is redefinition per se or merely the 2nd use of Substitution, whether redefining or not. I added one substitution and it worked fine. Added a second and it was not usable until S3 had been restarted.