It would be useful to include the time before oncall starts in the email subject. Currently it says “xxxx is going oncall for xxx Escalation Policy” and in the email body it says “xxxx is going on call for the following escalation policy in 24 hours” - this causes confusion if they do not read the email.
Some people don’t have preview activated (or don’t read the message body!), so it would be good to have some of this detail included in the subject (preferably at the beginning so that it doesn’t get truncated). e.g. “24 hours before xxxx is going oncall for xxx Escalation Policy”.