Formula to Sum across multiple, renamed, varible number of sheets

I’ve renamed all the sheets.
Each sheet represents a day of the month.
The names of the sheets are ‘01’ for the first of the month and ‘02’ for the second and so on.

I have a formula to sum like this : =SUM(‘05’.K7:‘23’.K7) where ‘05’ is the first day/first sheet and ‘23’ is the last.

This works fine however when i add a new day/sheet (ie ‘25’) the SUM function obviously will not include this sheet.

Is there a way to reference ALL sheets no matter how many there are. or to give a generic range like Sheet1 thru Sheet31, and have it work, even when there are only 5 sheets and there names have all been changed.

Alternatively, is there a way to macro an update to the cell containing this function that would give it the proper range.

I currently use a macro to add a new sheet and give it a name based on the date. how might i input the proper function to this cell from the macro.