Prevent a milestone from moving, regardless of predecessors? (flexible lag time)

I have a milestone date in my timeline (0 day duration). I would like to link it to a predecessor that is currently scheduled to finish a few days before the milestone, however, when I add the predecessor (Finish-to-Start), it moves my milestone date! (Moves my milestone date earlier, to occur the day after my predecessor task finishes.)

Is there any way to lock in that milestone date, regardless of predecessors?

I do not want to add in a set Lag time, because I'd like this Lag to be flexible. I'd like to be able to set my deadline, and then play around with predecessor task durations to see what works.

I've tried using Finish to Finish predecessors, and that keeps my milestone date stationary, but then moves my predecessors to stack up next to my milestone.

I'd love some tips on dealing with this! Thank you

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Robin Sherwood

Hi Cassie,

Thanks for your feedback. What you are describing in terms of "flexible lag time" is often refered to as a "constraint" there are six types: start-no-earlier-than, start-no-later-than, finish-no-earlier-than, finish-no-later-than, must-start-on, and must-finish on. Based on your description it sounds like you want either "finish-no-earlier-than" or "must-finish-on"

Smartsheet doesn't currently support constraints, but you are on the right track with the finish to finish dependency type. The way I would approach this would be to add an addtional milestone that you link to. This will allow your tasks and milestone to move a round a bit while keeping planned target date in place. Check out the image below. Also note that the dependency for the last milestone is actaully on it's predecessor, not the last milestone itself.

Hope That helps,

Robin

Screen Shot 2015-10-16 at 1.02.26 PM.png

Cassie

Hi Robin,

Thanks for the quick reply!

From what I can see in your example, your "Actual Go Live" milestone effectively has a start-no-earlier than constraint. (If you were to adust one of your "Work" rows to be longer, 10 days for example, then your "Actual Go Live" date would push out beyond the "Planned Go Live" date. But otherwise it aligns to the "Planned Go Live" date and won't go earlier.)

Is there a way to setup the predecessors such that the "Actual Go Live" date is constrained to finish-no-later-than the "Planned Go Live" date?

Thanks again, this is super helpful!

P.S. Are constraints on the list for future development for smartsheet?

Kurt

I think that introducing constraint functionality would be very helpful in Smartsheet. There are many times that I have a milestone that should start no earlier than a certain date, but I still want to honor any predecessors such that if they shift out, it will force the milestone or task date to shift out as well.