These docs are for an old release.
Info on upgrading to version 2/3
formatDates 1.3
Formats a date range (two Date objects) into a string.
$.fullCalendar.formatDates( date1, date2, formatString [, options ] ) -> String
formatDates uses all the commands from formatDate, but with two special forms:
{...}- switches to formatting the 2nd date
[...]- only displays the enclosed format if the current date is different from the alternate date in the same regards