Ciao Pan
I'm also here because of the tool from confusedbuffalo.
When correcting the phone number I'd also take care of deduplicating them from `contact:phone` and `phone` to only one of the keys.
I've done that in https://www.openstreetmap.org/changeset/174277232
Greetings,
habi

PS: I often use `phone` as it seems that this is the default of ID, but both are valid, in my opinion just not as duplicates...