Website emergencies have a reputation for being sudden, yet a surprising share of them are scheduled well in advance. A certificate lapses on a date printed on the certificate. A CMS release stops receiving security fixes on a date the vendor announced long before. A plugin licence renews on the anniversary of purchase. Teams that treat these as unpredictable end up fighting fires; teams that treat them as calendar entries do routine maintenance instead. Here are nine entries every website key-dates calendar should contain, with advice on how early to set each reminder.

1. TLS certificate expiry

An expired certificate turns a working site into a browser warning page. Many sites use automated issuance, which is excellent, but automation can fail silently after a hosting move, a DNS change or a changed validation setting. Put the expiry date of every certificate on the calendar anyway, with a start reminder at least a month before. The point is not to renew manually; it is to confirm that the automatic renewal actually happened.

2. Domain registration and DNS provider renewals

A domain is the one asset that cannot be rebuilt if it is lost to an expiry. Record the registration expiry, the registrar account owner and the payment method on file. If a card on file expires before the domain does, the auto-renew will fail, so add the card’s expiry date as its own entry. Set the first reminder to six weeks before the domain deadline so that a failed payment can be solved without drama.

3. Hosting plan and server renewals

Hosting renewals often arrive at a higher price than the introductory term. Log the renewal date and the cancellation notice period, because some providers need notice well before the term ends. A reminder two months ahead gives you time to compare options and to schedule a migration instead of rushing one.

4. CMS version end-of-life and major releases

Every CMS has a supported-versions policy. When a branch stops receiving security updates, running it becomes a risk that grows each month. Check your platform’s published release and support schedule and add the end-of-support dates for the versions you run, plus any announced major release. Reminders should be placed early enough to leave room for testing a staging upgrade, not merely for pressing an update button. For teams wrestling with how editors and developers share the work around those updates, the discussion of helping teams collaborate inside a modern CMS is a useful companion.

5. Runtime and language support windows

The same logic applies below the CMS. PHP, Node and database versions each have a support lifecycle published by their maintainers. If your hosting runs a version approaching its end of support, you want to know a year ahead, not a week ahead. Add the end-of-support date for each runtime in use and a reminder to review compatibility with themes and extensions.

6. Plugin, theme and licence renewals

Premium plugins and themes usually pair a licence with a renewal date after which updates stop. Letting a licence lapse means missing security patches while still running the code. List every paid extension with its renewal date and cost, then decide in advance which ones you will drop. A single spreadsheet can serve as the register, and the calendar carries the reminders.

7. Legal and policy review dates

Privacy notices, cookie policies and terms of service need a periodic review, and some regulations set their own deadlines for consent and documentation. This is informational, not legal advice, so the safest calendar entry is a recurring one: a scheduled review with whoever advises your organisation, plus an entry for any specific compliance date they give you.

8. Campaign, seasonal and content-refresh dates

Marketing has fixed dates too. Retail peaks, festival seasons, annual reports and product launches are events that content and landing pages must be ready for. Work back from each date to find when copy, design and QA must be complete, and set the start reminder there. Evergreen pages deserve a review date as well, so that outdated claims and broken references do not linger. The article on bringing SEO routines and asset management into one workflow pairs well with this one, since content refreshes are where those workflows meet.

9. Third-party platform and policy changes

Payment gateways, analytics tools, search engines and social platforms announce changes in advance: deprecated APIs, retired features and updated requirements. Each announcement carries a deadline. When one arrives in your inbox, copy the date straight onto the calendar with a note linking to the announcement, rather than trusting the email to resurface.

Setting up the reminders properly

Entries are only half the job. Use a consistent pattern so the calendar can be read at a glance.

• Two alerts per entry: a start reminder sized to the slowest realistic task, and a final nudge placed shortly ahead of the cutoff itself.
• One named owner per entry, with a deputy invited to the same event.
• A first action in the title, such as “Verify certificate auto-renewal” rather than “Certificate”.
• A link to the source, whether it is the vendor’s lifecycle page or the registrar’s dashboard.
• A recurring review once a quarter to catch changed schedules.

One more place to look: finance and compliance dates

If your site is run by a business, the accounting side has its own cycle. Filing windows and results announcements for public companies follow a public rhythm, which finance-education sites document. The finance-education site Stocks Mantra gathers a page of dates that matter to investors in its resources area. That is learning material rather than advice, yet it illustrates the discipline of keeping external dates in one visible place, which is exactly what your technical calendar should do.

A sample quarterly routine

Keep it proportionate. A five-page brochure site and a busy online store will not carry the same number of entries, and that is fine; the categories above simply tell you where to look.

Once the nine categories are in, keep the rhythm light. On the first working day of each quarter, one person opens the calendar, scans ninety days ahead, and checks three things: whether each upcoming entry has an owner, whether the start reminder is early enough given current workload, and whether any vendor has changed a date. Anything that needs real work becomes a ticket in your normal system, linked back to the calendar entry. The review takes about fifteen minutes and replaces a lot of anxiety.

What good looks like

Mature teams rarely mention their calendar because nothing dramatic happens. Certificates renew, domains stay registered, upgrades land on staging a month before they matter, and campaign pages are live on the day of the festival. The calendar does not remove the need for skill. It removes the need for heroics, which frees developers and editors to work on things that actually improve the site.

If you only have time for one step this week, export a list of every certificate, domain, hosting plan and licence you pay for, record each date, and set the start reminders. You will probably find at least one date that is closer than you thought, and that single discovery tends to justify the whole exercise.