Go to Admin > Settings > Calendars > Your Calendars and choose the 'Working Year' Calendar. From this page you will see a list of the years at
the bottom (e.g. 2011 - 2014). To add 2015 you should change the 'Num
periods' from 4 to 5 and Submit. This will add another year to the list
at the bottom of the page. Then you should check to see that the new year includes all the
appropriate Bank Holidays. You can do this by clicking on the Period
name for 2015.
This is the only required yearly task but doing it about now for the next year is
a good idea. Obviously you could add a few years by changing it to 7
for instance but if you go to far ahead the Bank Holidays won't be added automatically
(so you'll have to do this yourself) and this is a good way to restrict
leave being booked too far into the future before you've added rules for
that year or mandatory leave etc.