I have this problem as well, I assumed it was an IOS thing.
The thing about RideControl EVO that really annoys me is that the clock is only able to be displayed when you are navigating somewhere.There is no way to display the clock when you are just riding without navigating, even though the section of screen used to display the clock is empty.
The Navigation function is very nice, but it’s not particularly useful, for example, I can’t tweak the route to follow the bike path I like. Frankly, I probably would have gotten a bike without EVO given the choice, that way, if I ever decided to tune it, I could have used something less intrusive like a BadAss Box, plus I wouldn’t have had to worry about waterproofing issues.