Copy the link, do not just tap it. Tapping the link downloads a file that is frozen at today's schedule. Pasting the link into your calendar app's Subscribe field keeps it live, so date changes, postponements and cancellations arrive on their own all season.
iPhone or iPad
Copy the link above.
Open Settings, then Apps, then Calendar. On older iOS this is Settings, then Calendar.
Tap Accounts, then Add Account, then Other.
Tap Add Subscribed Calendar.
Paste the link in the Server box, tap Next, then Save.
Recommended: go back into that subscribed calendar and set Refresh to Every Hour.
Android or Google Calendar
On a computer, go to calendar.google.com. Google does not allow adding a subscription from the phone app.
In the left column, hover over "Other calendars" and click the plus sign.
Choose "From URL".
Paste the link and click "Add calendar".
On your phone, open the Google Calendar app, tap the menu, tap Settings, and make sure the new calendar is checked to show.
Google refreshes subscribed calendars on its own schedule, often several hours behind. Apple refreshes faster and lets you set it to hourly.
Mac Calendar
Open the Calendar app.
File, then New Calendar Subscription.
Paste the link and click Subscribe.
Set Auto-refresh to Every hour.
Outlook
Add calendar, then "Subscribe from web".
Paste the link, give it a name, then Import.
Put a schedule button on your phone's home screen
iPhone or iPad: open this page in Safari, tap the Share button, scroll down and tap "Add to Home Screen", then tap Add. Chrome on iPhone does not offer this.
Android: open this page in Chrome, tap the three dot menu, tap "Add to Home screen", then tap Add.