Strax Field Reports.

Strax Field Report was an umbrella title for a series of in-character advertisements in 2013 that featured Dan Starkey's Strax sending reports back to Sontar. These "reports" were about episodes of Doctor Who that had not yet aired, and thus served as advertisements. Indeed, in at least two of the reports, the character clearly was talking about out-of-universe things, such as the name of episodes and location filming. The "field reports" were all delivered to the public on the web.