In reply to M0LEP:
For instance, the rules in Kenya say that you
must add “/P” (or “/M”) if you are not at your declared address
I don’t remember whether it was stated like this in previous Spanish regulation, but this is the meanning that the /P has to me.
In my interpretation of /P, the P stands more for Provisional location, different to the officially declared as base location, rather than Portable, which might be interpreted more as walking while using a portable rig like a handie or a FT-817 with its rubber flex antenna for instance.
Best 73 de Guru - EA2IF