If you want your escalation rule to run only during certain period of time, you can add the following to your existing SQL clause:

(... existing SQL triggering clause) AND datepart(hour, current_timestamp)<'18'
AND datepart(hour, current_timestamp)>'7'
AND DATENAME(WEEKDAY, GETDATE()) <> 'Saturday'
AND DATENAME(WEEKDAY, GETDATE()) <> 'Sunday'

In this example, it will not get triggered after 6pm or before 7am, and it will not run on weekends.

Also, if you want to notify a user if, say, a record hasn't been updated for 14 days while being stuck at a certain stage, you can use this SQL clause:

 DATEDIFF(day,case_updateddate, getdate())>14 AND (case_stage=<1> OR case_stage=<2>) AND case_assigneduserid=#U