I wasn't even aware that 154.205 was used for a paging freq for DelCo Fireboard. The only dispatches I've ever been able to catch were on the low-band 46.48 (and that can be very sporadic depending on where I am in DelCo).
Yes, 154.205 is used for the County owned Motorola Advisor II alpha numeric pagers that have been given out to the companies. They have not made any info available as to cap codes etc. Mine pretty much stays in my truck or hanging off my work duffle bag, I still choose to carry my old reliable Minitor II (and the amplified charger is a must when sleeping with earplugs between nightshifts). The 911 folks have stated that they will continue to keep 46.48 active as long as their current stock of parts holds out, then it will be the digital pagers only.
The 170.150 frequency may still be in use, I remember hearing that in some parts of Upper Darby Twp the 154.205 was not cutting it due to some local interference and an alternate frequency was setup to cover members in that area, not sure if this is still the case but that 170.150 seem about right in my cloudy memory.