Working around clock face limitations

I am limited to creating a clock face for the Garmin Swim 2. There are severe limitations on what you can do in a watch face, which makes perfect sense because it is always on and draining the battery can be a real problem. 

One thought I had was to embed slowly changing data in the clock face application itself. This will only work if updates are installed automatically when syncing with the phone. I would also have to automate the publishing of the clock face app.

How do clock face application updates get installed on the watch?

Thanks