In this invited paper, we present utilization of free-space optical (FSO) link in overcoming a connectivity gap between the backbone and last mile access networks. The non-line-of-sight area is bridged by radio frequency (RF) link by employing relaying technology, while the FSO link is used to deliver transmission from the relay to the end user. Firstly, a brief recapitulation of main results in the field of mixed dual-hop relaying RF/FSO system is presented. Further, the performance of mixed dual-hop amplify-and-forward (AF) relaying RF/FSO system is analysed. The outage probability expression of investigated system is provided, considering variable gain AF relay when channel state information (CSI) estimation is imperfect. The Nakagami-m fading environment is adopted for RF hop, while the intensity fluctuations of optical signal are assumed to origin from both atmospheric turbulence and pointing errors. Numerical results are presented and validated by Monte Carlo simulations. Effects of different system and channel parameters are observed. It is concluded that outdated CSI used for relay gain adjustment has an important impact on the mixed RF/FSO system performance.