Here's everything you need to know about McDonald's all-day breakfast plans

McDonald's is going to start offering an all-day breakfast menu at several locations in San Diego next month, the company told Business Insider Monday.

If the test is successful, McDonald's could expand it to more restaurants.

The Big Mac chain stops serving breakfast at 10:30 a.m. at most locations.

"We know our customers love McDonald's breakfast and they tell us they'd like to enjoy it beyond the morning hours," the company said in a statement. "We look forward to learning from this test, and it's premature to speculate on any outcomes. We're excited to serve our customers in this area some of McDonald's great-tasting breakfast sandwiches, hash browns and other favorites all day long."

Testing all-day breakfast "makes sense," Janney Capital Markets analyst Mark Kalinowski wrote in a recent research note.

Some of the most "craveable" items on the McDonald's menu are the McMuffins and McGriddles, he noted.

But it could also cause major operational problems.

McDonald's stops serving breakfast at 10:30 a.m. in most markets because its grills aren't big enough to handle breakfast and lunch items.

"It comes down to the sheer size of kitchen grills," the company says on its website. "They simply don't have the room for all of our menu options at one time - especially considering we use our grill to prepare many items on our breakfast menu."