The process can be very quick if you have these string tie beads:
Tying the strings on the bridge part becomes extremely easy wit these.
It also gets rid of the risk of damaging the guitar from a string getting unknotted when tuning. I also have the strings to be 'strectched' when tying on the tuning machines having no allowance, so It just takes a couple turns of the machine heads to stretch the strings into tension. Takes me about 10-15 mins to change strings including light dusting and cleaning. I change once or twice a month.