Hey there, magenta5367531!
Welcome to our Support Community! I'm glad you came here to find answers with what's happening with our network in Iowa and Illinois; let's see if I can get you some answers. The majority of the I-80 drive headed west in Iowa is considered "partner coverage" which means that speeds and connections vary. While we'd love for phones to automatically select the fastest network possible, that's a development request via Android software engineers and the device manufacturer. The good news is that we are doing a TON of upgrades in the Iowa/Illinois area and adding a good amount of towers that'll be running on 700 mHz or in some cases adding 1900/2100 mHz towers. It appears that the site upgrades and new towers builds should be completed by the end of this month, but don't quote me on that only because sometimes there are delays due to weather, material availability, scheduling, etc.
I'm heading out on this route again this summer. Have there been any upgrades to either the Android system to address this issue or your partner coverage on I-80 since last summer?