In the telecommunication industry, the roll-out of a new mobile communication technology is a challenge faced periodically by mobile operators which are required to upgrade their infrastructure. In this paper, we consider the problem of determining the best strategy for the introduction of 5G on the market operated by telco operators. We focus especially on ensuring the most efficient timing to perform such upgrades on the network. Operators seek to delay the deployment costs, taking into account that infrastructure upgrades by other operators might let customers switch to such competitors. We formulate the problem in the form of a discrete-time timing game and we introduce game-theoretical solution concepts to determine the optimal choice in a competitive setting. We take into account logistical and normative constraints, set by the regulator. Both operators can track each other's 5G deployment, by observing the evolution of the quality of service, which is a piece of public information.