Yeah, I think I prefer ordinal over extended_month. ordinal is clear about what it actually does, extended has always been confusing for me and it makes some sense in the context of years (where it's also a term of art) but it's different here.

In the issue I said:

The one people should generally be using though is standard_code, but it is really tempting to reach for ordinal. So I feel like we should prefix all three.

That doesn't quite make sense to me: ordinal is already the disambiguator, it doesn't say code because it's not a code. All three of them have weird names, just that two of them have two-part names because they're also codes. I could call it ordinal_number instead if that brings them more in line, though personally I'm not sold on the value of doing that (but happy to do it if you find it valuable).

(clippy is still failing)