Hello,
I completed some testing and can only confirm your findings: once a Purchase Order has been received, I’m unable to link a Normal PO to a Blanket PO that contains the same item and vendor, even if I return the items.
Please add your Idea to the Ideas section of Acumatica Community so we may vote for feature improvements in future versions.
I found one related idea that could help prevent your situation: please vote to add option to use existing Blanket PO if one already exists for the same vendor and item user is ordering from:
Thank you.
Laura
Hello
We will check with our team on this and add our ideas.
Thanks for your help.