Formatting/locking/Unlocking range of cells

I need to create a grid that displays and accepts data based on a rolling 14-days, seven days prior to Report Date and seven days following Report Date.

The data is displayed in columns by date. For any column where the date is not in the same calendar month as the Report Date, I want to "grey" out and lock the cells, preventing data entry.

How would I code a VB loop to accomplish this?

I have attached a small worksheet showing what I am tryiny to accomplish.

Thanks,
SSGMiami