Moving from 4G LTE to 5G is an archetypal example of technological change. Mobile Network Operators (MNOs) who fail to adapt will likely lose market share. Hitherto, qualitative frameworks have been put forward to aid with business model adaptation for MNOs facing on the one hand increasing traffic growth, while on the other declining revenues. In this analysis, we provide a complementary scenario-based assessment of 5G infrastructure strategies in relation to mobile traffic growth. Developing and applying an open-source modelling framework, we quantify the uncertainty associated with future demand and supply for a hypothetical MNO, using Britain as a case study example. We find that over 90% of baseline data growth between 2016 and 2030 is driven by technological change, rather than demographics. To meet this demand, spectrum strategies require the least amount of capital expenditure and can meet baseline growth until approximately 2025, after which new spectrum bands will be required. Alternatively, small cell deployments provide significant capacity but at considerable cost, and hence are likely only in the densest locations, unless MNOs can boost revenues by capturing value from the Internet of Things (IoT), Smart Cities or other technological developments dependent on digital connectivity.