UDF for Attendance register

Hello,

I have used your UDF as shown below to report a date whenever an entry is made in a row of my excel sheet.

Function LastAttendanceDate(mDates, mTimes As Range)
Dim mCol As Integer
For Each cell In mTimes
    If cell.Value <> vbNullString Then
        mCol = cell.Column
    End If
Next cell
LastAttendanceDate = Cells(mDates.Row, mCol)
End Function.

What I need to to do in addition to this is to IGNORE the characters O (Thats a letter O), or a W and not to change the date if they are used. In other words the date of the last attendance must not change if either of these characters are entered in a row.

I have tried many things but I am now so confused I need your help.

Thanks in anticipation.

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