Shorten Long Formula

Hi There,

I would like to try and shorten a long formula that I am using to check about 25 sheets for a match.

I have attached an example of what I would like to do with just 4 sheets but eventually this will expand to over 50 sheets plus.

This is just a snippet of the code I am using, this only checks TWO sheets and I currently have approx 25 and increasing

=IF(COUNTIFS('Att 02-10-20'!$a$3:$a$4,F10,'Att 02-03-2020'!$F$9:$F$22,"y"),TEXT('Att 02-03-2020'!$F$4,"dd/mm/yyyy "),"")&IF(COUNTIFS('Att 04-03-2020'!$B$9:$B$22,F10,'Att 04-03-2020'!$F$9:$F$22,"y"),TEXT('Att 04-03-2020'!$F$4,"dd/mm/yyyy "),"")

If you open the attached example it should explain my requirements in an easier format.

Thanks