Hi, Noelle!
I am going to have to deliver "good news/bad news" to you but I'll try to be as magical as possible! Let's start with the bad news first and get it over with! If using Disney transportation, the 80+ minute estimate is probably right on. Buses do not go resort-to-resort so you would need to transfer buses at one of the theme parks.
Let's get some "good news!" A faster route would be hiring a taxi at your resort. You could be door-to-door in under 15 minutes. This would allow you sleep in, not have to wait for a bus, and your driver would drop you at the front door of Disney's Beach Club Resort for your breakfast. Sorry - one more touch of bad news - the taxi fare will run around $20, so budget that into your vacation.
Your options:
BUS: If you are going to rely on Disney transportation, stop by your lobby concierge the day before your breakfast and confirm what time the buses will start in the morning, and which theme park you should travel to for your bus transfer (this will vary based on your reservation time and which parks will be open that early). Allow plenty of time for waiting for the buses to arrive and travel time.
TAXI: If you are going to splurge on a taxi, stop by your lobby concierge the day before to confirm the procedure at your resort to have a taxi available for your morning drive to the Beach Club. If you use "car for hire" apps, you may also want to look into that service option.
Now I will end with some REALLY good news (I told you I would be magical!) The most important part is that you will be starting off your day celebrating your son's
birthday! Breakfast will be amazing and all his favorite Disney Pals will be excited to share in his special day. Enjoy!
Cathy