Yes, I have seen this also. To add more detail, I was playing Mirage and I started to channel my ult. My teammate Ivy picked me up before it completed.
When my ult completed channeling I teleported to where I had chosen, but immediately my character flew back through the air to Ivy meaning that my ult was wasted.
I think Mirage's ult channel should stop when this interaction occurs, instead of being allowed to finish. Either that or he becomes un-pickup-able while channeling his ult.
