@JenniferP - This involves a product level change to add this, or if possible, Lithium PS can do that for your specific instance. You can get in touch with support.
Technically you should be able to pick the "U.S. Central Time" option. (I acknowledge Canada is not part of the U.S. and correctly it should be correctly called "North American Central Time"). But in regard to the effect of this setting on your Lithium Community experience (formatting of time stamps within the UI and day start and end within LSI reporting) you will get the same experience as with a "UTC-6:00 Saskatchewan" option. 🕰️
If your community audience has a large enough population to warrant getting a dedicated setting entry for this time zone added. As @VarunGrazitti pointed out please get in touch with your Lithium account resource to learn how this can be get done.
