How can I tell if Xfinity is deploying DOCSIS-PIE for bufferbloat in my area?

DOCSIS-3.1 modems have the DOCSIS-PIE algorithm for reducing bufferbloat.  For uploads, the modem applies PIE.  The CMTS handles it on downloads to the modem.  If I upgrade to a DOCSIS-3.1 modem, will I get either PIE on uploads or PIE on downloads (I'm QAM, not OFDM)?

My understanding is PIE is enabled in some CMTS areas by Xfinity, but not others.  This leads to asking whether or not I can tell on the management page of a 3.1 modem if PIE is enabled or disabled for download and for upload?  If it isn't apparent to customers in the modem, how do I find out about the CMTS supporting PIE in my area?

For that matter, I am not certain that PIE on uploads is not always enabled for 3.1 modems and would appreciate someone explaining if PIE on 3.1 modem uploads has to be enabled by Xfinity.