I am not familiar with the Scheduler module but if you were creating a Saved Search, you could use a simple string such as <(84) updated><(y) equals yesterday>.I’ve attached an example for bib records (json file). You will want to make sure that the Include Record Information box is unchecked (otherwise, the Saved Search will likely be useless).
As I am not sure of the purpose you have for the file, I would recommend that you review the results to make sure they are exactly what you intended.
Yes. If you press y, or open up the available options It is a default for later versions of the software. I believe it (and all relative dates) became available with Sierra 2.0. If you don't see if showing up, I would suspect it is due to the version of software you are using.