on a recent QE, some of the items delivered for breakfast room service were not the same as what was served in the restuarant. For example, the room service grapefruit juice was the mucus colored presumably from concentrate as compared to the fresh squeezed dark pink served in the restaurant. Also, we were told that certain items were not available for room service as the ship was starting to run out, but there was still some availability at the Restaurant so the distinction of serving a grills guest for room service was not made in the room service kitchen.
But a few things we starting doing is preording room service from the Grills menu when our excursion is schedule to arrive around the time the restaurant closes, and when dinner service runs long to have dessert and coffee delivered to the room, or to the grills lounge if you have plans to meet other guests there.