I would ask day care if he was trained would they deal with it and not expect them to train. I mention this because my DD was trained at 19 mos and started a daycare they didn't work with the kids in her room but since she "was completely trained" they would let her into the other room to use the bathroom but wouldn't spend time training her. I would hate to deal with diapers longer than I had to, let alone discourage a kid who was that close to being trained. He is well on his way if he recognizes when he need to go and announces it.