How long exactly is a month pass valid?
A Global Pass - 1 month continuous is valid for train travel on each day during 1 month. The number of travel days you have depends on the length of the month in which you start using your pass.
July has 31 days, so the pass is also valid for 31 days. February has 28 days and a pass is therefore valid for 28 days.
Here are some examples:
First travel day 1 July: pass is valid from 1 July up to and including 31 July.
First travel day 12 July: pass is valid from 12 July up to and including 11 August.
First travel day 1 February: pass is valid from 1 February up to and including 28 February (or 29 February in a leap year).
First travel day is 15 February: pass is valid from 15 February, up to and including 14 March.