Hey Klint!
A very warm welcome to planDisney! Thanks for bringing your question our way!
I’m sure you’re looking forward to your vacation to “The Happiest Place on Earth!” And, it sounds like you are aware of the requirement for making an advanced
Theme Park Reservation. When making a reservation, you will select your starting park. At this time, your arrival window is “All Day.” This means you may enter
Disneyland Park at any time during the theme park operational hours. You are not required to arrive by a certain time of day or within a certain window of time.
But, because you have a Park Hopper
ticket, you may hop to
Disney California Adventure Park after 1:00 p.m. on the day of your visit. You are not required to make an additional theme park reservation to visit the second park or hop back and forth between both parks. But, as always, theme park admission is subject to attendance availability and theme park operational hours.
I hope this helps! Enjoy your vacation to the
Disneyland Resort!
Tiffanie