For my 2006 Jayco 29FBS TT, I "hand" clean using Protect-All Rubber Roof Cleaner its entire roof and its existing caulking area, let dry 48 hours, then apply Dicor Caulking. I apply 1 ft bead at a time and "feather spread it out" with my clean fingers. This stuff is self leveling and it will continue to gravity level to its lower areas. Thus, filling in wide / deep cracks (in existing factory caulking beads). I do max 12" areas at a time, and slowly work my way down the roof line. Or, around vents edges on the roof. Even though people don't see the roof area, I ensure its caulking is applied as if on a showroom case. re: Cosmetically perfect as well.
After waiting 7-10 days (for Dicor Lap Caulk to fully dry), I then inspect areas again. If all still looks great, I then apply Protect-All Roof treatment across the entire roof surface. It goes on like milk (re: using a hang sponge to spread it around the roof surface in full circle motions) and it flows into the smaller micro-cracks in the soft roof material. And, I lightly hand spread across the new Dicro caulk areas as well. Let dry for 24/48 hour - before its next rain day. After a rain, the rain water immediately beads up. Thus, showing this Roof Treatment stuff is repelling water. Some folks don't believe in roof treatment. Especially since its manual effort to apply. But after seeing positive results for many years, I apply Dicor and Protect-All Roof treatment every 6 months. Especially at our seasonal site TT - that's under treats (which love doing droppings).
Products I use are:
Good luck with your Caulking "tweaking" areas.