No, I don't think so. An Autofilter treats the entire "region" of a table as relevant. Since you have prefilled some of the columns all the way down 500 rows with a formula, then THAT is the current "region".
Hmm, having said that, the only reason it's doing that is because of the formulas. Since you're using VBA, there's no reason not to remove all those formulas and replace their functionality with a worksheet_change event that watches column B for changes. If you enter a new row value, the VBA would go and retrieve all the information you're currently using the formulas to accomplish in that row only, no further.
One way to accomplish that is to have the VBA enter the working formulas in those cells:
1) Remove ALL the formulas beyond row 4
2) Then put this code into the Admin Leave Tracker sheet module, replacing all the code that is in there currently:
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