The AWS Cloudwatch PERIOD function (in expression) 5x smaller in 24hrs time range

Don’t log. Graph it, e.g. TIME_SERIES(PERIOD(m1))

And play with variables, e.g. dashboard time range, Period and prove that CloudWatch PERIOD function is wrong:

whenever the time range is less than 48 hrs, the PERIOD will return 60 seconds vs. 300 seconds