I did this for a registry value, it should be similar. Here is all of my relevance.
if (exists key “HKLM\SOFTWARE\BigFix\CPM\client” of registry) AND (exists value “LastPatternUpdate” whose (it as time > now - 2*week) of key “HKLM\SOFTWARE\BigFix\CPM\client” of registry) then false else true
(it as date < date “14 Jun 2008”) of (preceding text of first “/” of following text of first “/” of it & " " & (it as integer as month as three letters) of preceding text of first “/” of it & " " & “20” & following text of last “/” of it) of date of bios
The statement not work correctly for BIOS earlier than 2000. We would have to modify a little.