How to freeze all work orders and purchase orders?

Hello,
We would to freeze all the work orders and purchase orders because we cannot process the MRP and MPS message types C, D, E, G and L but we want to keep message type B, so we cannot use the item freeze fences.

I've been through the Manufacturing and Distribution documentation and I didn't find a standard way to do it.
So, the only 2 solutions, I see, are:
Change DD default value for UNCD to Y
Or
Add some triggers on the tables F4311 and F4801 to create all the new orders with UNCD = Y

Do you see another possibility preferably in the standard functionality? If not, would you recommend to change the DD, add some triggers or something else?

Thanks for your help,
Best Regards,
Regis LITRE
Unix / Oracle / Oneworld Xe (7.3)

I would recommend changing the data dictionary to Y. That being said, our data dictionary is N. To get around this same issue, we created a batch job that runs prior to MRP each night that will freeze all open work orders. I would be happy to forward the event rules of the report.

Attached are the event rules for freezing work orders.

Attached are the event rules for freezing purchase orders.

All Released Work Orders are treated as Frozen by using R3482 Generation Type = "5" for Items with Planning Code = "1". This is standard functionality.

Hi,
Do you know if we can massively update UNCD (Freeze code) on opened purchased orders ?
I need to unfreeze 1000 Purchased Orders lines, indeed.
It would be really time consuming to do it with P4310.
Thank you