... Anyone else come across this issue?
The quick answer is 'Yes' but the problems were not exactly the same as yours - so far. You can find a handfull of recent stories (perhaps their OPs will point them out.)
I just had an engine light thrown at me while speeding up to traffic on the interstate with less than 5k miles. Also accelerating upward past 70 the whole truck was stuttering and not shifting into the next gear. I have the limited and am rather worried now
Be sure to establish proper documentation of the start of the problem with the dealer. Keep a paper copy of everything, Notes with time and date of who you talked to may turn out to be golden somewhere down the line.
Hope you both will keep your stories updated - many of us are close to buying, but these stories, though few so far, are pretty alarming.
Good luck, and I hope it turns out to be a minor fix and you're back out there Cruzin' again soon.