The departure days have been corrected to Tue & Fri. If you refresh, it may erroneously go back to Fri only (maybe some glitch with the official site). The timetable is current now - so refresh is not necessary.
Regarding calendar: Yes, thanks for noticing - the valid departure dates are now highlighted. These days are correct for intermediate stations as well. So, if you were looking for availability on this train from Bhopal, Wed & Sat would be highlighted, since the train reaches this station on the second day.