Besides classical performance indicators such as throughput and capacity, other metrics like reliability, availability, and latency are becoming increasingly important for designing and analyzing wireless networks. This work provides novel insights into how high availability can be achieved. For doing so, a preexisting model for detailed analysis of the signal-to-interference- plus-noise ratio (SINR) is adapted and applied to various intra-frequency multi-connectivity architectures. In addition, the impact of different carrier frequencies, i.e., 2.5 GHz and 15 GHz, is investigated as well. The developed models accurately capture the system performance and reveal distinct advantages and disadvantages of the investigated architectures. It is demonstrated that, especially, dynamic clustering mechanisms in combination with single frequency network transmissions are suited to achieve extremely high availability while using resources efficiently.