Error P0017
 

Good morning,
My 2010 LaCrosse sets the error code P0017 when starting. I can clear the code and drive for an hour and it never comes back. If I shut it off and restart, the code comes back.
It runs great. I recently had the O2 sensors replaced and this code started right then. Is there something the guy could have done changing them?
The code is crankshaft - camshaft position error for Bank 1 Sensor B. I assume bank 1 is the front bank, but which is sensor B, exhaust or intake cam?

Thanks for any help you can provide.
Richard