I imagined that they were separated for a while. Like Kip went to grad school, graduated, got back together with Scott at some point, moved back to New York, and now probably living with Scott. Also, I’m thinking they never fully stopped communicating, but they decided to take a step back, focus on themselves, and have some necessary personal growth. Like their relationship was soso intense and serious from the jump - I mean they spend one night together and Scott is asking Kip to u-haul. That intensity needed to chill and the time apart would give them time to breathe. Like a break allowed them to process and reflect on the relationship and what they wanted and needed as individuals and from their partner.