Takes at least 12-14 months to hit level 10, starting from level 2-3, without assigning Speed. Hard to be more precise with the random stops, and depending on the route traveled, but that's been my observation over the past years. I name my squads with the patrol start date so it's pretty easy to track. Squad "November 2016" is currently partway through level 8.
Edited By: Syn on Year 18 Day 348 2:47 ____________