PR Item Category changed after SC created

Hi,

SRM7.3

PDP Scenario.

I create a PR with Item Category = 'Blank' (Material PR) and it is successfully replicated to SRM as SC.

Now I change the item category in the PR as 'D' (Service) and put 1 service item.

I could see that system has generated XML for 2 items, as expected to be.

Perfect!

I have one item in XML with Action code = '02'... . which should update the main item.

I have one item in XML with Action code = '01'..... which should create service line item under the main item.

.. Perfectly fine!!

I compare all the segments of a good service PR XML and this one.

... All perfectly fine!!!

But the XML is failing to update the Shopping cart... XML fails with "Interface Data Contains Errors". Is this support in standard scenario?  Are we allowed to change the item category in the PR after the shopping cart is created?

Your quick answer please.....

Thanks,

Ganapathi