I was idiot-checking some advice I was about to give (meaning I was the idiot needing to be checked) when I ran into this. There’s an earlier mention of this problem from January 2016, so I am going to assume that was fixed long ago and something similar has broken since then.
In the following screenshot, {Date}
is a looked-up date field, while {Month}
, {Day}
, and {Year}
are formula fields that simply call the function indicated with {Date}
as the parameter. (That is, {Month}
is a formula field with the formula MONTH({Date})
, and so on.) Note the results for {Day}
.
I then modified {Date}
's configuration, changing it to a date field. Here’s the result: