In one one of our scenario, when we add material to Sales Order and save with Requirement Type(under Procurrement Tab of Sales Order) , in APO there is no planned order or only planned order which is dynamically pegged created because the ATP Tree in APO is not being converted. There is no pegging relevant item create(e.g. Planned Order). When we are checking the persistent ATP Trees in APO (/SAPAPO/ATREE_DSP - ATP-Trees) we can see that they are not converted automatically. They are still there. If we do it manually via transaction (/SAPAPO/RRP_ATP2PPDS - Conversion ATP Tree Structures -> Production Planning) it works. Afterwards the Planned Order is available and fixed pegged.
Why is APO not converting the ATP tree automatically ?
I also checked the scheduling horizon for conversion of the ATP Tree and it is correct: Is there any relation with Check Mode setting under ATP tab in Material Master?