derivedDataType ServedUserIdSelectionDT

EcimDerviedString with pattern restrictions. Allowed values are:

PPreferredId - Served identity is the same as received in P-Preferred-Identity header. If that header is not present, the identity is fetched from the From header.

alwaysUseDefault - Served identity is the default identity in the Implicit Registration Set pointed out by P-Preferred-Identity header, or if that header is not present. The identity is fetched from the header.