(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?
(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.
I've joined a company as a scheduler and their philosophy doesnt make sense to me. They tell me if the activity is completed, relationships doesnt matter. For example, Activity A is predecessor to Activity B with FS relationship and no lags. They say it is ok for activity B to have start and finish dates ahead of those of Activity A, as long as both activities are completed. They do that all over the schedule and always leave the original relationships.
I believe it is wrong to do that even if activities are completed. Can anyone please help me understand why I am right/wrong..
Thanks
Raj
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You are correct to worry about this approach. In my opinion, not correcting logic you know to be wrong is lazy planning.
Consider this example, a live one from a project I’m currently working on
(NB: UXO survey is unexploded ordnance survey –a standard requirement in UK when your digging in areas that were heavily bombed during WWII)
Original Plan: Earthworks FS(0)> UXO survey FS(0)> Underground pipes/ducts FS(0)> Prepare surface and blind
Change: UXO survey was carried out before the earthworks
Result without amending the logic: Underground pipes/ducts and blinding can be done before earthwork has started, which is clearly wrong.
Some software (eg Primavera) has different scheduling options (progress overide vs retained logic) which can affect how out of sequence (OOS) logic is calculated, but none are guaranteed to give a correct schedule unless the logic is amended to reflect reality.
Rafael also makes an excellent point that when OOS does occur, it is important to understand how and why this happened, and what impact the change could have on the rest of the schedule. It could be as mundane as the example above, or as serious as wet commissioning and oil refinery before the fire suppression system is ready.
That an activity finished it does not necessarily means there are no successor links that are still active. If these successor links have lag they might still be active and now invalid or in error, same as the original logic was, for whatever reason, usually a change in plans, not uncommon when the logic used was preferential logic.
Note that preferential logic might exists in SF relationships as well as in any other type of relationship, common when use of lag or splitting of an activity is done with the wrong perception there is no possibility of preferential logic in FS relationships, when in reality there might be on both options. If you need the activity to be continuous you do not split it, a common error of those who advocate for FS relationships only, just keep the lag as a better preferential option.
It is good practice to fix all out-of-sequence occurrences and explain why the change in plans if need be.
In the absence of preferential logic all schedules for any given job would be equal.
I guess they are called out of sequence activities. I am getting plenty of reading material when I search using that term. Anyway, thanks in advance for anyone who attempts to answer my question.
Email: PPadmin@planningplanet.com
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