Yes, making sense. So he's losing an hour sleep per night because you're putting him to bed at the new time but he's waking at the old time?
If your routine was stable before the clock change, so you know it's all as 'right' as it could be then you can force the WU time to move by putting to bed later for a few days. I had to take my LO past his BT to make WU later because his body clock was so set on that WU time rather than night length.