We were together every single day for our travels. We included 3.5 months travelling in Asia and 1.5 months of living in a campervan in New Zealand (and we were together for months before that time too). Then we got a lease together and have lots of evidence from then on. For the travel time we sent in ALL of our accommodation bookings, all of our flights, our matching passport stamps, our individual credit card statements showing we were taking turns paying for things until we were able to open a joint account, evidence he was added to my Canadian credit card long before we actually got back to Canada, anything we booked that had both of our names on it so some buses in Asia, some entry tickets in NZ, a letter from his parents who met us out in Sri Lanka for two weeks, a letter from my friend who met us for two weeks in the Philippines, a letter from a mutual friend who was in South Africa with us when we met and who we spent Christmas with in NZ a year later, a letter from my parents, the 20 photos, screenshots of social media with both of us in it at recognizable landmarks with date stamps... and a timeline referencing all our various proofs. I'm not really sure what else we can submit at this stage so just bracing for the potential of a refusal.
The PFL is very specific that the proof is to be for the previous 12 months from when you apply, not newer current documents, otherwise we'd have lots to submit.