Using a countdown timer to launch macros

I have commercial software connected to a betting exchange. The prices, volume data etc are loaded directly to an excel spreadsheet. There is a timer such that when one race finishes the next race, in time order, will load automatically. On another worksheet "Bet Angel", there is a countdown timer in cell F4. It counts in minutes and seconds down to official race start time '00:00:00' and then goes onto a negative countdown until the actual race starts.

I have macros fired manually by trigger buttons on sheet "Price Order" called Copy_Race and Trigger_Bet. What I would like to do is trigger both macros automatically at a specified time, "let's say 00:00:00". I've tried the following, for one of the macros, without success (you experts will probably laugh?):

Private Sub Worksheet_Change(ByVal Target As Range)
If Range("Bet Angel!$F$4").Value = TimeValue("00:00:00") Then
Call Copy_Race
End If
End Sub

Finally, because the Global settings will display a new race worksheet within a few minutes, I need the macro to rearm, as it were.

Thanks for taking the time to read

Re: Using a countdown timer to launch macros

Thanks John_w, I didn't end up trying your solution. I doubt if it would've worked on the 'Price Order' sheet. I found a solution but it had to be placed on the 'Bet Angel' sheet as that's where the feed comes in to. Unless you had a copy of the commercial software you probably wouldn't have sussed it?
Cheers