The fm350gl i guess gets default CA policy. Default is eutran3+ngran78+eutran7+eutran1 in my case. My s23 gets eutran20 or eutran32 ( SDL ) additionaly. My guess is that the ISP has special profiles for the high end smartphones, so that they can CA some bands more. Tech wise the fm350gl should also have no problem adding another band. It could take in my case eutran3 another 10mhz, 8, 20, 32, but it does not. In that case my guess is that the enodeb/gnodeb does not allow more.