What I mean by my thread title is that I used a guide on here to get a modified carrier file to allow built in tethering support. I'm now having service issues with the local cell tower in my area so yesterday ATT registered me to a different tower and it fixed the issue. Today I checked Signal app again and sure enough, it's back on the problem tower. 3G speeds are sucking again. So I'm wondering if the cell tower registration is strictly server-side or is it an actual file that's being sent to my phone which the modified carrier file might be interfering with.