Ok. Well, given the nature of the routine, this question is kind of ambiguous. Maintenance in this case may be considered maintaining a certain weight (since the routine suggests it's a weight loss routine), or it could mean conditioning level (since this routine involves a significant amount of metabolic conditioning). Or, maybe it's both.
Let's examine the possibilities.
After you've finished your routine and you have achieved a weight that you wish to maintain, you could simply cut out the conditioning altogether and reduce your caloric intake to match the needs of your physique. You'll notice muscle atrophy since you aren't conditioning any longer, and you'll have to taper caloric intake accordingly.
Conversely, you could try to be formulaic about your conditioning to match the caloric consumption of the last few weeks of your R4FL routine. In this case, you would need to try to keep your diet as constant as possible as well.
Let's assume it's both: you continue with your current diet, and for lack of ideas, you continue repeating the last few weeks of the routine. Unless you're dumping tons of refined starches and sugars into your body at every meal, you'll probably continue to lose weight. Those types of interval training sessions are extremely demanding. (If I may interject my own experience, I've seen 1000+ calories burned in the span of 20 minutes of high intensity intervals.) Furthermore, I think that it would be difficult for you to repeat your intervals at exactly the intensity you performed them at the previous time, just because you'll be in better shape. You'll perform them better, faster, and with more calories. Since intervals also introduce an anaerobic element to your training, you'll also be putting on muscle. Muscle require more calories to "own and operate".
It's difficult to answer this question exactly. I suppose ultimately when you finish this routine, you'll want to decide what you want to do. What type of exercise do you like doing? Do you just want to not be fat? Do you just want to run 60 minutes? Do you like doing intervals? Do you want to do both? Do you want to do neither? If you keep it up, the fat will stay off -- and likely continue coming off. If you don't keep it up, you'll have to play a game of weights and balances to eat just the right amount. In the long term (if your goal is strictly aesthetics), the type of routine you do will start to shape your physique in different directions. Distance running will give more of "stringy" physique, where intervals will give you a more "lean" or "fit" physique. If you're bored of running, maybe try doing something like following the crossfit.com main website's daily workout routines (there's pretty much something new and challenging every day -- check here for a scaled version of the workout of the day). I can refine my answer for you given some feedback.
