When IHOP announced last week in a cryptic tweet it would change its name to IHOb, the restaurant chain aimed to draw attention to the “mystery” of what the letter might stand for.

On Monday, it revealed the “b” is for burgers and the name change is temporary, part of a marketing ploy to launch a new menu. Along the way, the chain inadvertently revealed something else—that many of its customers don’t even know what the P represents.