Oil appetite

[Rootripper]

My 01, 210K, recently had the crankcase ventilation as well as all other components on the intake manifold replace. Purrs like a kitten. Prior to work it used about a quart of oil for 1000 miles. For six weeks after the work it used no oil, I was a happy man. Last two weeks I had to add oil twice, quart each time. No puddles. Using Amsoil Euro 0W40. Any opinions on what might cause this? Planning to ask mechanic who did the work, and planning a west coast road trip.
Thanks in advance for any help.
Mike