You can use the URL from arguments module, a field decoration (dictionary attribute ref_contributions), or a UI Action linking to show_schedule.do to invoke the Schedule page.

For example, the On-call calendar module generates the calendar from the following URL: 
$ocf.do?sysparm_start_date=2016-03-01&sysparm_current_view=monthly&sysparm_include_view=monthly,daily
This URL takes the user to the monthly calendar view dated March 1, 2016.
  • The URL component sysparm_current_view = monthly || weekly || daily determines the current calendar view. If sysparm_current_view is given an invalid or empty value, it defaults to monthly view and rewrite the URL to that view. Valid values are monthly or weekly or daily.
  • The URL component sysparm_include_view = monthly,weekly,daily determines which calendar views are available. If sysparm_include_view is given invalid or empty values, only the valid views appear. If all values are invalid, the default three views appears and rewrites the URL to those views. Valid values are monthly, weekly, and daily.
    Note: The sysparm_include_view is only available for the new on-call calendar view.
  • The URL component sysparm_group_id=group_sys_id determines the specified group to filter on. If sysparm_group_id is specified, it filters by the specified group. Valid value is a group sysId.
  • The URL component sysparm_start_date=2016-03-02 determines the date based on which every view appears. If sysparm_start_date is specified, it opens the calendar contesting that particular date in which every view is selected. The format is YYYY-MM-DD. If an invalid format or date is specified, it uses the current date and rewrites the URL to that date.
Note: The sysparm_zoom URL component has been replaced with sysparm_current_view in OnCallRotation only.