Disabling automatic refresh for snap from store

I’m trying to understand how to see if the snap refresh.timer changes actually stick. When I run sudo snap set core refresh.timer=sat,3:30, I still see:

admin@J82ZB02:~$ sudo systemctl list-timers --all
NEXT                         LEFT         LAST                         PASSED       UNIT                         ACTIVATES
Mon 2018-03-12 03:13:47 PDT  4 days left  Wed 2018-03-07 13:01:42 PST  22min ago    snapd.refresh.timer          snapd.refresh.service