They'll keep them based at more heavily defended aerodromes, well outside the range of Russian Lancets, which are rumoured to have a range of up to 70km now (which is an impressive upgrade).
An F-16's range is 925km on one tank of fuel, without drop tanks. That range increases to over 1200km with a fuel drop tank. That means Ukraine can base them extremely far from the front lines, where only Russian longer range missiles can strike. Those bigger, longer range missiles are also easier to intercept, particularly when you up something like a Patriot Battery, supplemented by an IRIS-T battery around the base.
Furthermore, Ukraine has underground hangars / hangars built into hills at some of their aerodromes, where they can keep their most imporant aircraft safe at all times except taxi, departure and landing. They're not going to be leaving F-16s sitting on a tarmac / ramp somewhere, unless they are hundreds of KMs away from the front lines, at aerodromes covered by several layers of air defense.
Furthermore, F-16's don't have to be close to the front lines to be effective. Ukraine intends to use its full capability as a weapon's platform, from range. HAARM missiles have a range of uo to 150km when fired from and F-16. JASSM cruise missiles have a range of up to 370km for the standard version and up to 1000km for the extended ranged variant. Furthermore, the F-16's can intercept both missiles and enemy aircraft / helos with their AIM-120 AMRAAMs which have a range of 100-110km. An F-16 can carry up to 6 AMRAAMs and 2 AIM-9 Sidewinders as a full weapon's payload.
In short, Ukraine has no interest in flying their F-16s close to the front, or basing them inside of Lancet drone range. As the F-16s arrive, you'll see them become more daring and aggressive with their remaining Mig-29s and SU-27s, as they'll become obsolete within their inventory.