Worried that the plan's not tough enough. It seems (on paper!) a lot easier than the Samantha B210K podcasts on here which I've also had a look at.
Here's the plan:
I'm following it as it's a 6 week plan and that fits nicely with my race date. I would like to do it in under 90 minutes, but really just be happy to run/jog the whole thing (no walking).