Brooke I have been going back and forth on that issue myself for a while. We thought we had the later wakeup (which we moved all in one go) then after a while we got early wakings again, but that was with Xmas and guests etc. So now I have moved it again...bed time - for naps I do stretch, but follow tired signs mostly, so they probably didn't move a whole hour in one go. Then if last A time is quite long, I do not give in, but am prepared to spend all my time with her helping her get to bedtime. In the mornings now, she is still waking at 5, but the last couple of mornings has then dozed on and off til 6 when I will take her out of the cot. I am going to persevere. If the evenings are a struggle, then she will either come for a walk in the sling or stroller, or have a very long bath as she is always happy in there. Baby Einstein helps too. So I have moved bedtime in one go, but naps are generally when she needs them anyway, I don't have set times for those, never have had and the timing and length varies from day to day.
Looking at your schedule though, I would go out, leave the house, to prevent having that 1st nap so early. It is easier to stretch A times when you are not at home. Go for a walk. That being said, around this age, Zara stopped being quite so sensitive to overtiredness when it comes to naps - will Colin just take a short nap if you keep him up to long?