Switch to Creating An App - Progress and Problems

I have switched from constructing my Linux server to building an Android application for the school.

This app will be designed to retrieve daily-updated information from a server. The problem I'm having with this, is when I try to access testing info through the school's WiFi on the app from my server at home, it seems it will sometimes access a cached version (since it is retrieving a .txt file through a URL). I assume this is because all non-school devices on the WiFi go to the 'guest' network, which I'd think receives all the bandwidth that isn't being currently used (i.e. the guest devices get a lower priority than the school's devices), so when there's not enough to be able to connect to that URL for updates, it just accesses the cached version instead.

If this is what the problem is, I think my best solution is to set up the server at the school (as the plan was anyways) and have the app recognize when it is connected to the school's network, and if it is, connect to the server for updates through LAN instead of internet to (hopefully) avoid the caching problem.

After I solve this problem, I have to remake the interface to use a fragments system, which will allow a lot more design & navigational features, and then start coding the rest of the PHP forms that gets filled out to update the information the app gets from the server.