Macro code assistance to edit the year in multiple cells.

Greetings! I'm looking for assistance that would via a macro change the year affiliated with dates in row 1; cells D1 through BM1 for whatever requested year the user wants. As well as any dates in column A, from A2 down. If a cell is blank it would remain blank. This macro should only apply to the specific worksheet intended and not alter any other worksheets in the workbook. Ideally I'd like to have a separate macro for January, and a separate one for February, March, etc. , but the February would only work for the February named tab, etc. The macro cannot affect the month and day specified, but just the year.

Ideally each year I would start a new year out using a blank version of the previous years workbook but would need to convert manually each date, which takes forever as my main workbook has a sheet for each month. I've attached a very small version/sample workbook, for anyone willing to offer assistance.

Thanks to anyone willing to assist!