The new underground plumbing for the master bathroom met the old vent pipe. The old sink drained into this pipe and the new sink will too. But I had to reconfigure the pipe for the new sink.
I replaced the black pipe up to the old vent pipe with new 2″ white PVC and moved the drain from the front to the rear of the vent pipe.
The new plumbing will run along the wall behind the vanity and connect under the sink. Simple change but it made room for the new shower wall.