Dinesh,
Deactivate all Integration models that contain any Sales Order, SD Scheduling Agreement, Sched VMI, and Req Reduction objects. ECC transaction CFM2.
Delete all inactive Integration models that contain any Sales Order, SD Scheduling agreement, Sched VMI, and Req Reduction objects. ECC transaction CFM7
Search for Sales order, SD scheduling agreements, Sched VMI, and Req reduction against your test material/plant CFM5. THERE MUST BE NO MODELS ASSOCIATED WITH THIS MATERIAL/PLANT for each of these four objects.
Deactivate the runtime model (all objects, not just the above 4) using ECC report RCIFIMAX (you can reactivate later if you want).
Delete all superfluous filter objects (all objects, not just the above 4). ECC report RCIFIMDL.
Delete all sales tables and LiveCache entries in SCM using report /SAPAPO/SDORDER_DEL, third tab, select 'Delete all orders'
Check //RRP3 in APO against your test material/plant. There should be no sales docs of any kind..
Create a new sales order in ECC (do not use an existing order). If this order still goes to SCM and updates //RRP3, then you probably have a non-CIF custom functionality that is moving Sales orders to APO.
Best Regards,
DB49