Yes and no depending on which Lightning Lane Product you are wanting to book.
Lightning Lane Single Pass attractions are reserved for the most popular attractions in the parks. Each ticket holder can purchase up to 2 Lightning Lane Single Pass attractions per day. This is valid for one ride at the chosen return time. They can be spread throughout any of Disney’s theme parks but you must have a ticket with a valid Park Hopper option to use them.
Lightning Lane Multi Pass reservations are limited only by attraction capacity. More popular attractions, or those with limited capacity, will book up far sooner than other attractions. Once you have scanned into your first attraction you can reserve your spot on another attraction depending on available capacity. If your first reservation is later in the day you are able to choose another attraction 2 hours after the allocated park opening times and then every 2 hours until the park closes or capacity is reached at all attractions.
The timings of your reservations are crucial to getting the most out of Genie+, but it also depends on other factors. The number of Lightning Lane positions is fixed per hour and per attraction but availability will depend on attraction popularity and crowd levels on the day.