How To Create Filter That Limit Results (Max Rows)

I have a data bound datagridview on my form. I need the datagridview to sort by oldest date, and then return only the 150 oldest. The goal is to export the 150 rows with the oldest date to a .csv file and then update the date column to the current date for only those 150.

Here is what I have so far:
Dim appPath As String = Path.GetDirectoryName(Application.ExecutablePath)
Dim tdate As Date
tdate = Today.Date
'sort datelastemailed by oldest to be emailed first
DataGridView1.Sort(DateLastEmailedDataGridViewTextBoxColumn,
[Code] ....

I can get it filter by the column "status" and then sort by "datelastemailed". I can also get it to export only those 150 to the .csv file. My issue is that I need only those 150 to have their date column updated to today's date and then saved to the database. The only way I can see to get that done is to set a max number of rows for my databound datagridview and then loop through each row in the date column. How I can create a filter that limits results?