To switch stations simply means to go from one language to next during your interaction with another speaker who may also be bi or
multilingual. People "switch stations" to add a bit of context on the subject matter or topic they're talking about so that the listener can fully comprehend the speaker. The speaker also does this as a way to relate to their listener(s) and make them feel connected. The phrase/term originally derived from the multitude of radio and TV stations, in South Africa, that are being
broadcasted in different tongues/languages for specific listeners/viewers to read. So if you change from one station to the next, you would hear the new speaker on your
telly or radio speak in a different tongue than the predecessor from the other station.