Interesting.  You are right.  I didn't know that.

§1.168-8 doesn't really say that, but Publication 544 does confirm that it is generally ordinary (I haven't traced where that is based on, but I'm assuming that is correct.

https://www.irs.gov/publications/p544#en_US_2021_publink100072287

As for how to enter it, I don't know if the program has an easy to to all it or not, but a work-around might be to just change the "placed in service" date and make it short-term.