We catch up with Belfast-based musician and promoter Nathan O’Regan about the origins, success and upcoming – downright unmissable – festive installment of monthly invitational session Songbook on Tuesday, December 8th. Hi Nathan. First of all, for those not familiar with Songbook, briefly tell us about your original motivations for starting the night back in the summer of 2017. Songbook began with the intention of filling what I saw to be a massive hole in the Belfast music scene. Having started gigging here in 2013, I was lucky to have fallen in with an incredible group of players but was…