Your trip is in August, right? Then you have plenty of time. You can start making reservation 2-3 months in advance.
At the moment there have been no announcements when and which character meals will return.
Best value for a character breakfast was the pilot they did right before Covid with the princess breakfast at the Auberge, I hope they will bring this back. Your other option for a character breakfast is Plaza Gardens, both in
Disneyland park.