There are so many ways you can format time for things like Expiry or ActionPlans in CGrateS, this is mostly just a quick reference for me:

• *asap (Now)
• *now
• *every_minute
• *hourly
• *monthly
• *monthly_estimated
• *yearly
• *daily
• *weekly
• mo+1h2m
• *always (What?)
• *month_end
• *month_end+1h2m
• +20s
• 1375212790
• +24h
• 2016-09-14T19:37:43.665+0000
• 20160419210007.037
• 31/05/2015 14:46:00
• 08.04.2014 22:14:29
• 20131023215149
• “2013-12-30 15:00:01 +0430 +0430”
• “2013-12-30 15:00:01 +0000 UTC”
• “2013-12-30 15:00:01”

Stolen from: https://github.com/cgrates/cgrates/blob/8fec8dbca1f28436f8658dbcb8be9d03ee7ab9ee/utils/coreutils_test.go#L242