I've just been looking forward into the end of the programme (biggest problem - trying to run before I can walk!*) and week 7, 8 and 9 has increments from 25 to 28 to 30 minutes of running.
Now, given that by the end of week 7 I'll be running 25 mins, surely the jump to 30 mins wouldn't be that hard after that? I think I might jump from week 7 to week 9.
Mostly because I have a half marathon to run in May though!
(see what I mean about running before walking?!)