Continue playing the strongest board you can make, while setting up to transition into Ahri when you find her. You can continue running the sharpshooters and add in some Mystic and Spirit units at this point.
Additional comp tips
Chosen Vanguard is preffered for this comp as if you have a Chosen Mystic, you will have to drop either Shen, Zilean, or Cassiopeia for a unit like Hecarim who will not provide much in the late game.
Sunfire Cape is a strong item to build early in order to stay strong or to try and win streak. If it's late game, you should look to build Morello over Sunfire as it provides more with enemies having more units.