How to write if Condition for this

[#1]

Hi

the qvw which i gave works like..it runs on every sunday at 6pm.

if i run today (30-4-2014) it will take the timesmtmap of last week sunday

now what i want  is

if i run the qvw at 30-4-2014 at 12pm it has to take the timestamp as 30-4-2014 12:00:00 and run.

after the last weekend of this month(27-4-2014) it has to stop and

for remaing three days it has to run on month end(30-4-2014).

please modify the master calendar according to that.