How to delete & replace Principal resource on Work definitions using FBDI?

Summary:

I want to do bulk changes on work definitions, by replacing the principal resource with another resource.

For this, I'm first trying to delete the existing principal resource, then loading another FBDI to create a new principal resource.

But the issue is, it's not allowing to delete the principal resourse. Even thought of removing the principal flag (making it as NO) & then delete that resource. But this is also not allowed as there should be atleast 1 principal resource for an operation sequence. And the catch is, without deleting this resource we can't even add another resource as Principal using Fbdi….!