With regard to the discussion about Pingdom price increases, one alternative I use is Uptime Robot (https://uptimerobot.com/).

I also use Pingdom and consider it the Cadillac.

To John's comment about wp-cron, there are external services that provide this, taking the load from the server. easycron is the one that we use, and there a list of them on Pantheon's site (https://pantheon.io/docs/wordpress-cron/)