[B.A.T.M.A.N.] interface preference

Is there any manual way to prioritize a wired interface over a wireless interface? It seems to do so naturally at first, but if I unplug and replug the Ethernet cable a couple times when testing it will stay on wireless. Is this considered an optimization or a bug, and how can I make it so it should always choose the Ethernet, even in multi-hop situations? For example, Babel uses an "rxcost" metric for each interface to manually increase the cost of a route on each interface.

Thanks for your help.