The timeRequired example given 'P30M' probably shall mean "30 minutes". However, 'P30M' actually means a duration of 30 months, which I do not think was the intention. The correct way to specify a duration of 30 minutes is 'PT30M'.
The timeRequired example given 'P1H25M' is invalid, as "P1H25M" is not a valid duration string. The correct way to specify a duration of 1 hour and 25 minutes is 'PT1H25M'.
The timeRequired property: http://schema.org/timeRequired
Description of ISO8601 durations: https://en.wikipedia.org/wiki/ISO_8601#Durations
correcting examples in timeRequired. Fixes #1469