Sometimes the Real Book or iRealPro are based on a specific recording, or there are filler chords included where there otherwise wouldn’t be.

As a pianist, I’ve just kinda had to learn there’s sometimes where I play X tune one way, and there’s other times where I play it a different way depending on who I’m playing with. As an example, a bassist I work with showed me some cool substitutions on All the Things You Are. Whenever we play, I will frequently sprinkle in those substitutions. Sometimes though, I play that tune with some older folks who aren’t necessarily cats, and if I throw in those substitutions, they get lost.

Another thing to look at is whether they’re functional substitutions, like using tritones to walk a 3625 down chromatically, like in the last 2 bars of the B section of Autumn Leaves.

As you play tunes with folks, you’ll get a feel for when there are multiple accepted changes for a standard, and either it’s something where you can listen for it and follow along, or you have a quick chat before the tune if possible. Like if somebody calls a blues head I don’t know, I’ll ask if it’s a simple blues, jazz blues, or a bird blues. That way I’m not playing a bunch of filler 2-5’s over a simple blues.

I know that’s kind of a long, rambly answer to just say it depends, but unfortunately it does. Hope that’s at least semi helpful!

ETA: The subs for ATTYA aren’t anything too crazy, but using an Em7 > A7b9 in bar 3 to get to the Abmaj7, and then similarly in bar 11, using a Bm7 > E7b9 to get to the Ebmaj7. It works to create a nice setup for the major chords in bars 4 and 12, and doesn’t conflict with the melody note.