The short answer is, no there's not. EE used to offer a 3G indoor "signal box" that many people refer to as a booster but was in reality a 3G picocell.
However, with the availability of WiFi-calling as a preferred solution, and the impending 3G switchoff (industry-wide), those are no longer available.
In your case I'd be minded to query why your landlord is switching WiFi off at a particular time - perhaps you could ask them if there's an alternative solution to whatever their issue is.
