The original intension was for the kangaroo to just be a brief point of interest. Maybe it was being transported by a vehicle that crashed. Then they discovered that the cast, crew, and viewers really liked the kangaroo and they are weaving it into the story. They say we'll know more by the end of the season.
They also mentioned that the show in which they catch up with themselves will be aired on April 29 and that the number 137, which is the number of seconds in 2 minutes, 17 seconds, will be significant.