I wouldn’t worry about them walking around, they may take a few bites but they can’t do much damage before the petals are down. BUT, the minute the petals fall you need to get on it! I often am a day or two late and the damage can really rack up. Now I am stuck in a one-week 3-inch rain period so my Surround is not going to work well. Thats one downside of Surround.
I can tell my population is down a bit this year, usually I find about a dozen in the trees to. So far this year I have only found one live bug. I love it when they go crunch