delivering an excel pivot with one slicer already chosen

Hi, i stood up a relational sql server receivables table with a column called "AsOfMidnightDate".   I'm ok with ssis so this isnt necessarily an ssis question.  I'd probably use ssis to automate delivery of the following.   The table entries on month end midnight dates is most interesting but data is recorded daily so the list of date slicer choices is going to be long.

What i'd like to do is either on the fly or using a previously hydrated pivot in excel over this table, deliver to my user a version of the xlsx that upon open would use as a slicer the month end date that just passed.    Or some really simplified way of reducing the number of date choices so it is a user friendly thing to select the month end just passed.   I'm even wondering about a flag that is "pre chosen" indicating this is a month end (dates would somehow be sorted descending), that way she can use the pivot in multiple ways by flipping that slicer.

does the community have any ideas?