Diablo works exceptionally well on Cannabis Ruderalis (autoflower). The only difference is when using natural sunlight (outdoors) or in a greenhouse, it takes a bit longer to flower as the sun dictates the timing.

When you reach weeks 3-5, just keep going on that nutrient recipe level (for those weeks) for another few weeks until you start to see white hairs or indications that flowers are developing. At that point you would switch to week 5 to 6 and just follow along as though you were on a 9 or 10 week schedule.