Yesterday starting around 9:00 EDT PHL Tower was evacuated (I believe for smoke) and TRACON was on back-up transmitters. Listen to the PHL Tower and Approach feeds from about 9 - 10
AM EDT.
The ILS was un-reliable so the RNAV approach to 27R was in use. They were also holding at JALTO normally used for the ILS 27R (6.1 out)
Thanks to Ed for helping point this out