ccalworkhours not giving correct result on Friday.

Question

Hi Members, I am trying to calculate the working hours between two different time using calworkhours function. It is giving perfect result for all the days except on Fridays. I have check my calendar setting as well . Friday's setting is same as other working days. I have pasted the Screenshot of Calendar and Expression along with it's result. 
 EscalationCalendar Image : Expression Rule and it's Result Image : 
 
 I am expecting 6 hours but it's giving 2 hours and it is same for every Friday. Please help on this ASAP.

Mike Schmitt · Answer

Yeah, I was strictly referring to the example Sanchit posted here. For the examples you posted at the top, GMT conversion doesn't even seem like it could be a factor into it (unless your system calendar's timezone is much more offset than I suspected). 
 Out of curiosity though, what happens if you wrap the initial inputs in "local()" and/or "gmt()" before calling the rule? One of these converts a datetime value TO local time FROM gmt time, and the other does the opposite, and I never reliably remember which one is needed at a given time, but i do know that they ARE needed SOMETIMES.

Mike Schmitt · Answer

"3" seems like it'd be the valid result, if not for the calendar "end time" set at 5 pm. It makes me wonder whether it's sneaking in any of our normal unintuitive GMT conversion either before or after the results are evaluated?

Sanchit Gupta (Xebia) · Answer

Smart guess. It seems like the timezone offset is first removed from the inputs and then the hours are calculated. I tried adding timezone offset to the the dateTime and it gave expected result.