You should be out of Navi between 903 and 910am since you most likely will be let in a few minutes early. If you walk briskly, about a 5 minute walk to KS. Be careful, they sometimes will not open up the "shortcut" to Africa and you will need to double back towards Tiffins. 5-7 minutes wait/load time for KS. KS takes 18-21 minutes.
Remember that the FP window is actually 5 minutes before/15 minutes after the official time...............so you really have an 80 minute window to ride.
Use this data to craft your plan.