saving parts with seqenced name suffixes -p1,-p2,-p3...

In Muse3 I saved exported .musicxml files for each part using names like
myPiece-p1.musicxml
myPiece-p2.musicxml
myPiece-p3.musicxml
This was convenient for further processing I do with a script to convert the files to Sonic Pi format

In Muse4 there doesn't seem to be such an option and the parts are differentiated by the instrument name
eg
myPiece-Soprano.musicxml
myPiece-Alto.musicxml etc and I have to rename them for my further processing each time they are exported. Is there any way to use the names that I had before?

I tried renaming the displayed name on the score for each part, hoping that that might be used but it wasn't.
I quite often have ten parts or more and it becomes very tedious.