Yes, and it was because my little one dropped a nap. I thought it was too soon too, by she now naps from midday or 1pm for nearly 3 hours sometimes, or at least 2 hours minimum
My little one dropped a nap and is only down to one 2 hour nap a day and that has really helped with our bedtimes x
Could it be that your routine is the same but he isn’t? Is he needing more or less sleep? I find if my child wakes up in the night it’s because he hasn’t had enough daytime sleep