Subash,
I assume you are talking about MTS and not MTO. I further assume you are not using fixed pegging, which obviously does not allow automatic 'switching' of supply elements. Please confirm.
I see no reason why standard CTP wouldn't meet your requirements. When you tried it, what exactly were the results that you found unsatisfactory? For that matter, what makes you think that GATP 'gives' stock to one sales demand, and 'gives' a planned order to another sales demand? GATP product check doesn't normally do any pegging of supplies..........
Best Regards,
DB49