MP3 Tag / Album artist / band

In the past I had some issues with replaygain by album tags if one track had for instance an additional guest artist.

Solution was to look at the album artist which I always set the same for each full album, then it's ok for the artist itself to be different.

I had made a note to myself (as i don't clean my tags often) to have replaygain also check the BAND tag, and specifically not "album artist".

To my confusion I just open mp3tag and my files all show a question mark below BAND and ALBUM ARTIST is filled in for every file. Has something changed that I missed in iTunes or mp3tag or was I wrong all along? I just changed preferences so replaygain now looks at ALBUM ARTIST

What's actually written to the ID3v2 tag is a TPE2 frame.
Some time ago Mp3tag changed the label of that frame from BAND to ALBUMARTIST.
So just use ALBUMARTIST instead of BAND.