I've worked in tech long enough to know incompatibilities happen and am not looking play the blame game. I just want my phone to work reliably when I leave wifi; at this point its either upgrade to a 12 on 2Degrees, or change network and keep my current handset. Thanks in advance.
I honestly couldn't say, sorry. I work in core network design, not handsets. FWIW I have an iPhone XS and haven't had these problems with it myself.