I imagine it does. My 2016 21BD came with it. Should be a red key-looking switch under the propane tank(s).
Or it could be a push-pull switch inside near the fuse box.
Sometime between 2012 and 2016 they seem to have dropped the push-pull in favor of the red key.
1988 Coleman Sequoia - popup (1987-2007)
2012 Roo19 - hybid (2012-2015)
2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10