My son, who is now almost 11 months dropped his catnap around that time. It was hard because he would end up being real tired an hour or so before bedtime because he wasn't use to being awake from 4pm to 8pm, 4 hour stretch. Even now he still gets cranky sometimes and I just end up putting him to bed 30 min earlier.
Is your little one really cranky around this time? It might be he just is getting older and will not take the nap anymore. He may take about a month to get over that crankiness. What I did was move his first nap later by 30min and then his second nap to a bit later in the day as well so he wouldn't be such a monster come evening. Here is my schedule:
8am wake eat
10:30am nap until about 12:30pm
3pm nap until about 4:30-5pm.
7:30pm bedtime
It evens the awake and sleep time out more so he isn't awake for 4 hours, instead it is just 2.5 or 3 hours.
Here read this link, it may be helpful::
https://babywhispererforums.com/index.php?topic=64837.0