Is it possible to disable sync over the internet?

I sync a couple libraries to my iPad and realized this week that when I connect to my mobile hotspot (and also launch Plex, as I sometimes do on my lunch breaks to watch synced videos) it is syncing and eating up my limited hotspot data. I will definitely try to be more careful and make sure I complete a sync at home when I add something to the library, but I know it’ll happen again where I forget and burn through a gig or two without realizing it. I’m wondering if there is a way to only allow syncing when I am at home over the local network. Is this possible? I can’t seem to find any setting for it when I poke around in the server settings.