My ds's progress, or could well be my optimism, has always been up and down, not huge dips, but enough for me to feel hopeful about his future one minute, and then feel really pessimistic and sad about his future the next. Just lately he's stimming alot, so his autism appears more obvious, could be stress and his stimming helps bring himself into his own privte world, IYKWIM. At 3 he was described with complex needs with not much hope functioning in any classroom, now although has 1-1 he is in mainstream and is coping relatively well, but come Juniors he might not be able to cope with mainstream at all.
I remember watching Jacqui Jackson and Luke and the second youngest, (is it Jo?) on Trisha, was impressed how well the children coped with sitting there in front of an audience. My ds would have totally flipped.