IBS Events is a plugin for creating and scheduling events for IBS Calendar display.
The custom post-type “ibs_event” is added to the WordPress admin.
While it is not essential to have IBS Calendar plugin installed for IBS Events to work, there is no native way provided by IBS Events to otherwise view the events created, outside of using the admin facilities.
As noted in the readme.txt this plugin uses the rrule.js engine for recurring events. When the calendar.js is activated it will make an ajax call to the server to obtain all ibs_event instances and store them client side. When Full Calendar requests events for the current calendar view calendar.js will scan the loaded ibs_events for appropriate events to display.