QUESTION

Dear Mr P6 Civils,

When running our calculations in P6 8.2, we noticed that under schedule options, the calendar for scheduling relationship lags was set to Successor Activity Calendar.  I assumed is should be scheduling off of Predecessor Activity Calendar. Is the default Successor Activity calendar? If so why? I would assume you want to base your lags off the predecessor activity. This will affect your schedule especially if you are using different calendars.

The issue for us is that for those schedules that were created in 7.2 the default seems to be Predecessor Activity Calendar. I have no idea why it is nor does anyone else in our group.

Regards…

SUGGESTED ANSWER

My current settings show the default on P6 8.2 as the Predecessor Calendar. That make the most sense, especially in SS relationships. You also have the choice of Successor Calendar, 24 hour Calendar and Default Project Calendar.
 
If you are ever any concerns about the lag calendar setting, just change it and see how it affects the schedule.  In general lags should be kept to a minimum and the effect of the calendar used should be minor. (Running multiple float paths up to the Successor Activity and plotting it on a Gantt Chart would be an excellent visual aid in examining the effect.) 

Hope this helps.