Does this new piece of information mean an extra episode of Doctor Who this year?

Although that makes each instalment at least five minutes longer than in previous runs some fans, used to 12-13 entries in recent years, grumbled at the reduction in episodes.

But perhaps things aren't as bad as they at first seemed. Because some new information has emerged suggesting that there might actually be more Doctor Who this year than we were expecting.

In an official advert inside industry publication Toy World Magazine, BBC Worldwide has placed a full-page tease (on page 69) for future Doctor Who tie-in merchandise that promises “More than 11 hours of new content in Autumn 2018,” far more than we were expecting.

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Even allowing for the fact that the series 11 premiere will run for a full hour, the amount of time allocated for the new episodes is only eight and a half hours, so where are the other two and a half or so coming from? The BBC are remaining typically tight-lipped – but there are a number of possible answers.

For example, it could be the case that this extra time includes a Christmas special, the likes of which Doctor Who has aired yearly since the series returned to TV in 2005. Now, there had been some speculation that there would be no festive episode this year due to it not having been mentioned in the series announcement, but for production reasons Who-letide adventures are sometimes included as part of the series order for the following year, which could explain its absence from discussion thus far.

So maybe an hour-long Christmas special is coming after all. Then again, that still wouldn’t account for all the extra time, and its arguable whether an air date of 25th December would count as coming in “Autumn 2018”.

So what else could account for the extra time? Certainly, some of it could come from an extended series finale, which isn’t a rule (and wasn’t suggested in the initial announcement) but has become fairly common in recent years. Alternatively, the number of episodes or their length could have changed somehow, which is technically possible but seems extremely improbable.

More likely, the 11-plus hours includes the likes of tie-in online videos, be they short “prequel” scenes setting the tone of the episode, spin-off sketches like the Pond Life miniseries that accompanied the 2012 series (and, perhaps not entirely coincidentally, was written by Chibnall) or perhaps even behind-the-scenes offerings in the vein of Doctor Who Confidential and Doctor Who Extra.

If we had 15-minute behind-the-scenes videos for every single episode that would provide more than the missing two and a half hours. It could even be that tie-in YouTube series like the Doctor Who Fan Show (which interviews cast members and writers after the episodes) count towards this runtime, all adding up to the series length we were expecting but with a few online accoutrements.

Of course, until more announcements are made we can’t know for sure one way or the other – but in our heart of hearts, we know we’re all secretly hoping there’s a secret extra episode hidden in there somewhere. After all, only Doctor Who could have a series that’s secretly bigger on the inside…

Doctor Who returns to BBC1 this Autumn