Look at humidity as an averge, you just spent 10 days with humidity 68%, if you now spend th enext 8 days with humidity at 45% your average will be somewhere around 59% which is still too high.
You need to correct for the overly high humidity so you want o run lower to bring that average down.
whether or not you should run dry depends on where you lvie and what your RH is like in the room you have the incubator in.
If you can control the humidity aim for 30% humidity, make sure you mark out the aircells at least and then check back on day 14 to see how the aircells are going and again on day 16 and 18, that way you can correct if you think too drastic changes are happening.
Another thing to mention, humidity isnt a number that keeps chicks alive, the point of the humidity is to make sure the eggs lose enough weight, and the aircells thus grow, so there is no number that just works, its a balancing game.