[BBDodge]

In BB13 there were 2 gentlemen carrying the job title Senior Producer: Cam de la Huerta and Oliver Manley. Presumably one of those individuals has gotten himself another job for this summer.

As Sid says there are others more senior that the senior producers. The Executive producers (who get quoted in the Press Pack) were Denis O'Connor, Suzy Price and Katy Smith. The Creative Director is Nick Samwell-Smith. That was Philip Edgar-Jones old job and he was usually credited (blamed) for the important issues of the show (such as housemate selection).

Edit: Ah, I see Sid has updated his post with similar info! Nick Samwell-Smith is creative director for the whole production company (Initial). Denis O'Connor didn't get a 2nd credit for Creative Director on the credits of BB13 that I checked.