Cron job fails to run per schedule

Hi Community,

I have a periodic job running with the following cron:

# Deploy the website every Mon, Wed, Fri, Sat, and Sun at 5:00 UTC
periodic_deploy:
triggers:
    - schedule:
        cron: "0 5 * * 0,1,3,5,6"
        filters:
        branches:
            only: master
jobs:
    - site

This job, however, does not always run. Who knows why?

Date Ran?
Friday February 19
Wednesday February 17
Monday February 15
Sunday February 14
Saturday February 13
Friday February 12 did not run
Wednesday February 10
Monday February 8
Sunday February 7
Saturday February 6
Friday February 5 did not run
Wednesday February 3
Monday February 1
Sunday January 31
Saturday January 30
Friday January 29 did not run
Wednesday January 27
Monday January 25
Sunday January 24
Saturday January 23
Friday January 22 did not run
Wednesday January 20
Monday January 18
Sunday January 17
Saturday January 16
Friday January 15 did not run
Wednesday January 13
Monday January 11
Sunday January 10
Saturday January 9
Friday January 8 did not run

So the job often doesn’t run on Friday, even though I have 5 defined as the day of week.

Just to clarify, I’ve added the cron schedule to CircleCI in late December and not just recently. So from my understanding it should run on the missed Fridays in the above table too.

Do you have an idea what can cause this? Thanks!