What in the world is SMART'S WSU hybrid bus doing Downriver?

[mtburb]

A half-hour ago, I decided to walk over to the corner of Fort Street and Eureka Road along the Wyandotte-Southgate border for one thing: bus-fanning.

Not long after I arrived, SMART #223[[65?) was heading towards Metro Airport operating route #125. Around this time, I decided to cross Fort Street and see if there were benches to sit on on the Southgate side of the intersection, so I pressed the button to cross the street [[the button is a recent addition due to the recent reconstruction project), but the signal still displayed "don't walk", but then, something appeared that I never expected: One of SMART's hybrid buses!

So I decided to get a dozen pictures of the bus as it operated #125 in the opposite direction towards River Rouge [[even though this was during the evening peak period, I don't know why this run didn't want to go all the way to Detroit!) As it got closer, I noticed the colors on that bus indicated it was the Wayne State bus! It then crossed Eureka Road and stopped next to the Walgreens store to pick up a few people [[who were, I assume, excited to ride a hybrid bus, possibly for their very first times). This ends the story and the beginning of the on-topic portion.

I am asking a question on how SMART's WSU hybrid bus decided to operate a Wayne County route today, I noticed on another thread here that it was supposed to operate Oakland County routes and that the U-M bus was to be used for Wayne County routes [[including #125). So I am unsure how the WSU bus ended up coming down here today instead.

BTW, the bus is SMART #3006, a 2011 Gillig Low Floor with hybrid and Gillig BRT-styled-front-and-rear-ends [[if you don't know what a Gillig BRT is, you'll find them on the streets of Ann Arbor, operated by AATA) options. Here's a photo to prove the point of this: