ATP Plan and Production Plan does not show same results

Hi All,

We are using ATP plan and Production Plan both are set as Capacity constraint and Plan Options are same for both the plans, However when we run the plan and perform ATP Inquiry from Source Instance it gives an earlier date and for the same item the planned order suggested by Production plan have a later date.

Usually Business would like to see the date when any Assembly can be manufactured and they do it by checking ATP inquiry and then place the sales Order however Production Plan can not fulfill the same item on the date suggested by ATP plan.