A group of 30 people is large enough that broadcasting matters. The way you share the calendar determines whether the next edit reaches everyone or not.
Here is the pattern that works.
Step 1: Publish a subscription, not a file
The first decision is the only one that matters long term. Publish the calendar as a subscribable link, not a one-time download.
A subscription is a URL the calendar app re-reads on a schedule. A download is a copy that never updates. The first time you edit an event, the difference shows up. Subscribers see the new version automatically. People who downloaded a file are stuck with the old one.
Calfeed publishes subscriptions by default. Skip any tool that hands you a single download.
Step 2: Send one link
Send the calendar link once. To everyone. In one message.
The message is short. Three sentences.
"Here is the schedule as a subscribable calendar. Tap the link and pick your calendar app to add it. Every change I make later will show up on your calendar on its own."
That is the entire message. Do not attach a PDF too. Do not write out every event in the body. The link replaces both.
Step 3: Include a sync-help page
About 20% of any 30-person group will not know how to subscribe to a calendar. They will tap the link, see an unfamiliar screen, and either bail or save it to the wrong place.
Send a one-paragraph sync-help message after the link. Or link to a help page. Calfeed includes a sync-help surface on every public calendar page that walks subscribers through the steps for Apple, Google, and Outlook.
The goal is zero "I cannot add this" replies.
Step 4: Stop messaging on edits
The biggest mistake group organizers make is announcing every calendar edit in the group chat.
You do not have to. The whole reason you used a subscription was so the edits push themselves. Every time you announce a change, you train the group to ignore the calendar and watch the chat instead. The calendar becomes redundant.
Reserve announcements for changes that are time-sensitive within the next 24 hours. For everything else, edit silently. Apple subscribers will see the change within an hour. Google subscribers within a day. That is fast enough for nearly every weekly schedule.
Step 5: Watch the subscriber count
Calfeed shows you how many devices have subscribed to each calendar. The number tells you whether your share message worked.
If the count is below 50% of the group size two days after sending the link, your message did not land. Resend with a sync-help reminder. Pin the message. If the count is still low, the group does not trust the format. Send the chronological list once and try again next season.
If the count is above 80%, the format is working. Do not re-share. The link is the same forever.
Make a calendar and try it on one group.