The above will trigger the conditional format
for all empty* cells within A2:D5
after 24 hours from the reference date/time in A1

The asterisk for "empty" is referring to the ensuing para
i.e. the 1st line in the following para should read as:
*If there are formula cells within A2:D5
.....

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Rgds
Max
xl 97
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GMT+8, 1° 22' N 103° 45' E
xdemechanik <atyahoo<dotcom
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