I can elaborate a bit on the strategy that I made for learning it all.
This was a bit special because I joined a band where many of the songs were already on their set, we probably picked up 10 new ones over the last year or so but the rest was material that they already knew.
So initially I had to focus on learning all the new songs. We rehearse every Monday, and I split it up so that I would learn 5-6 new songs each week. So after a couple of months I had a first version of all the songs. This was really a lot of work as well, of course it got a little easier once I had managed to "catch up" with the other guys..
For a while the band would then pick at random from all 40+ songs at each rehearsal... but that was a bit too much for me. So instead I suggested that we split them into small 10-13 song sets, and we then rehearsed those mini sets in rotation.
Next step was then rehearsing ONE "performance set" each week, so approx. 17 songs. That still leaves us time to work on some songs, if they are not 100% as we want them.
And finally, before a show we have a few weeks with trial runs of the entire concert from start to end... in this "mode" we don't stop if there are mistakes, but instead rehearse how to deal with these small mistakes (which WILL happen live) without the audience noticing (too) much...
As for how to make time for it all - it's just a hobby for me, and I also have a family. But I do try to play the guitar at least 30 mins each day, usually more.. most of that time playing some of the hardest songs. Otherwise it's just about playing them enough, then they'll eventually be internalized
