Gruu or Oubound support in PJSIP

I am having problems using TLS towards a Mitel installation, and have gotten a request to enable either “gruu” or “outbound”.
Does anyone know whether these SIP options are supported in PJSIP?
I am currently using Asterisk v. 18.0.1

chan_pjsip does not support GRUU or Outbound. For connections, however, it will reuse the same one if one has been established on outgoing. For inbound if “rewrite_contact” is set to “yes” then the inbound connection will also be reused for outgoing traffic.