Assistance in updating formula for DATE functions - eg DateValue, Day, etc, for Leap Years

To Whom It May Concern

I write to seek assistance in writing a formula for recognising and adjusting "DATE"-based formulas to include adjustments for Leap Years, please.

Please find attached an example spreadsheet of how I intend to use it.
Please note, Sheet Name: "Income & Cash or Debit Expenses", is the PRIMARY sheet; Cell A3, "Home and Utilities Sheet", is LINKED to the previous sheet.

"(IF(DAY('[Sheet Name]'!$A$3)<>365," etc, this refers to the number of days in a year (obviously); could anyone please show me how to write a formula that will automatically calculate and adjust for "leap years", ie 29 February 2024, 29 February 2028, 29 February 2032, and so on...

Please ignore:

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#REF!

Thank you, Matthew Hinds.