Sheet modified time not updating when form response added

[David Tod]

This is not particularly a GAM thing, although I suppose it could be. I have a form that updates a sheet, but when a form response is added, the sheet's modifiedTime does not change.

This is a recent behavior since July 20, 2023. Before that, form responses did update the sheet's modifiedTime.

I am using

gam user myusername print fileinfo myfileid

to get the modifiedTime of the sheet.