At first, VoLTE will be used to deliver "Rich Communications Services" (which look like something similar to what Voice over IP/Video over IP outfits offer today) rather than completely replacing narrowband voice. It will be awhile before Verizon is willing to commit to that, due in part to LTE outages in late 2011.
On the flip side is MetroPC, which has pushed VoLTE as hard as it could.
Then there's Sprint, which will stick to voice over 1x for the foreseeable future, but routes Direct Connect over IP. Sprint's latest DC incarnation seems quite similar to one facet of RCS over LTE.
Factory reset your Eero and redo everything from the ground up is what I'll say.
Something about the eeros current configuration is blocking the A4 and just doing these Config edits are not helping much.
So factory reset it to the basics and make sure the A4 works with that. Then slowly add custom settings and rules while ensuring the A4 is operational.
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