I'm giving the RunDouble app 5-10k plan a go, it gets you able to run 10k in 6 weeks from the point of graduating C25k. Tonight's pattern is 5 min warm up then 5 repetitions of 8 mins running, 1 minute walking. That's a total of 40 minutes running which I can manage fairly easily I reckon. Should cover about 6 to 6.5k in that time. Looking forward to a new challenge!