cutting groves was once allowed on sch. 40 and thicker. i think they did away with that 10-15 years ago?
as far as the gal. couplings. i don't know the contractor. i was there just for a sewer inspection on the weekend and the plumbing contractor was not there.
i would think that the copper coated ones are required. it might be they were out of stock and will substitute the iron ones with copper coated when they get them.