Responses

Yes, they are ageing, but as drope said in another comment, it was least than 2 years, I think In one ch they stated that it had been one year since kyouko joined the company
Btw in Conan only 9 months had passed since the beginning lol (they said it canon in the manga "recently") it doesn't have sense I know, but in the lastest chap they are keeping the time storyline pretty much at least lol
I started reading this in elementary school. Will this never end?? Are they even together yet? Don't tell me they'll get together on their deathbed right?