Why do schedules suffix the name with UTC?

When I create the following schedule using a String:

CRON_TZ=Canada/Eastern 0 7 * * 1-5

It appears as:

CRON_TZ=Canada/Eastern 0 7 * * 1-5 UTC

In the web UI:
image

The schedule works as expected (weekly at 7am eastern time).

Side note: if I try to duplicate this schedule and use the string with UTC as a suffix:
image

I receive the error:

Invalid schedule spec: Year is not in range [2000-2100]

image

I’m trying with the latest temporal (I believe) in my local environment:

temporal version 0.10.5 (server 1.21.4) (ui 2.17.0)