@adrianw:
I’m using the also ring (immediately) feature in the AA servers. No SIP in the phone, it’s just a normal telephone call from AA over EE to my wife’s mobile.
Indeed the handsets don’t need any configuration, so I don’t know what’s going wrong - N300 and handsets just not seeing one another so my wife reported, but I would need to take a look myself.
My bonded system does indeed weld the three connections into one seamlessly; applications have no way of knowing that there are actually three pipes underlying the one apparent one. However given the fact that the upstream speeds of the lines are very mismatched - 0.65 Mbps upstream on line #1 and 0.4 Mbps upstream on line #4 - I wonder about possible packet reordering, and certainly substantial jitter, which I can measure. I should retest this some time and see what the truth is. I could look out for packet out-of-orderness though by grinding my way through a connection traffic capture - god I hate that though.
That’s the problem though, seeing as it works so well as is, I’m too lazy to spend ages with AA debugging things.