A higher per average wait time in April does not mean the park was less crowded October. Wait times are no longer good indicators of crowd levels, especially with the horrible maintenance issues Disney has been having. In April, people are strictly visiting Disneyland to visit Disneyland, not participate in seasonal offerings. In October, people are visiting Disneyland for the decor, seasonal and costumes characters, seasonal food offerings, and merchandise (and of course, the rides). The stores are packed. The restaurants are packed. The walkways are packed. The character lines are insane. Just look at the wait time for Haunted Mansion Holiday. It’s not unheard of for the wait to be over two hours for that ride! The wait in April won’t top 30 minutes.
We went several times during that time period in April and in October. The most “crowded” April day on whatever historical crowd calendar you are looking at did not look or feel anywhere near as crowded as any day in October.