According to RTD in The Writer's Tale it does. It's why we always get casting announcements at the most inconvenient times, like announcing Eccleston's departure when they did. BBC tries to get an official announcement before the story goes to tabloids. Once it's in the tabloids, if someone asks BBC about it, the Charter compels the BBC to answer, and forbids them from lying. So they make official announcements about these decisions knowing it's basically providing official spoilers to the public just to avoid this situation.I'm pretty certain that particular directive in the charter doesn't preclude misdirecting the audience to avoid spoilers.
RTD goes on in The Writer's Tale about how he doesn't agree with this attitude and if it were up to him he'd gladly lie and provide disinformation to preserve spoilers, but doesn't because he knows the BBC are obligated in this matter and would overrule him.