The default P&ID Segment Breaker (in PIP) has Spec identifier annotations either side of the break.
However, when the break is applied to a P&ID process line it does not change the line spec on the downstream side of the break to "?".
It does however reset Service and Size fields for the downstream side of the break to "?" on the Line Tag annotation.
Can a control be added to the Segment Break symbol that enables the setting of the annotations presented and the associated data fields to be reset to "?".
I am trying to reproduce what you described in your post. Are you placing the Spec Break from the tool-palette directly onto the SLINE? Or are you using the SLINE's context menu to add a break?