Friends recorded this album --https://alisonperkinsandnicolasbrown.bandcamp.com/album/all-... -- with A somewhere in the neighborhood of 360Hz.
That's so low, it's more like playing the piece a three semitones lower than an alternate choice for A4.
If the piece was in A, it would be more like playing it in F# (while still using A=440).
(Of course if you did that, the "sweet-spots of 12TET and its off-notes would be different, than if you played with A=360)