Combine formula's without overwriting.

[FROGGER24]

I have these two lines of code that I would like to combine so it does not overwrite a cell if it has a value in it
Range("A2:A" & Cells(Rows.Count, 3).End(xlUp).Row).FormulaR1C1 = "=IF(ISNUMBER(SEARCH(""PBO"",RC[3])),""S"")"
Range("A2:A" & Cells(Rows.Count, 3).End(xlUp).Row).FormulaR1C1 = "=IF(ISNUMBER(SEARCH(""VS"",RC[2])),""B"",""S"")"

Thanks in advance

 

[Fluff]

Could you please explain what should happen in the following situations
1) col B has VS & col C has PBO
2) col B has VS & col C does not have PBO
3) col C has PBO & col B does not have VS
4) neither of those terms exist