# Seasonal releases, sandbox preview and release updates

*Platform Development Lifecycle and Deployment Architect Study Guide · Planning · Last updated October 26, 2026 · https://www.certifyforce.com/study-guide/platform-development-lifecycle-and-deployment-architect/planning/seasonal-releases-sandbox-preview-and-release-updates*

How to de-risk the three seasonal releases: plan backward from published upgrade dates, place sandboxes on preview or non-preview instances around the cutoff (Release Type, Request Non-Preview, clones), handle package uploads during the preview window, test release updates before sandbox test periods end, and turn release notes into communication and phased rollout.

- Certification: Salesforce Platform Development Lifecycle and Deployment Architect
- Exam section: Planning
- Study guide: https://www.certifyforce.com/study-guide/platform-development-lifecycle-and-deployment-architect

**Official exam objective:**

> Given a customer scenario involving a new Salesforce release (Summer, Winter, Spring), recommend the appropriate strategy to mitigate risks.

## What the exam expects

- Build a release readiness plan that works backward from the published sandbox and production upgrade dates, with regression testing on a preview sandbox.
- Decide whether each sandbox should be on a preview or non-preview instance, and what to do before or after the cutoff: refresh, Request Non-Preview, or clone.
- Predict which orgs can install a package uploaded during the preview window.
- Schedule release update test runs so sandbox testing finishes before its test period ends.
- Use release notes Feature Impact filters, super users and phased rollout to communicate changes.

Key terms: **preview instance** (sandboxes here get the next release several weeks before production; Help says 6 weeks, Trailhead says 4-6); **non-preview instance** (sandboxes here stay on the current release until production upgrades); **cutoff date** (the last moment a create or refresh can land on a preview instance); **Release Type** (the Sandboxes page column showing preview or non-preview); **release update** (a Salesforce change to existing behaviour with a Complete Steps By date and an optional test run).

## Key facts

| Fact | Detail | Source |
|---|---|---|
| Seasonal releases | Three a year (Spring, Summer, Winter); upgrades automatic for all customers | [Release Process](https://trailhead.salesforce.com/content/learn/modules/sf_releases/sf_releases_start) |
| Preview length | Help article: 6-week window; Trailhead unit: approximately 4-6 weeks. Teach "about six weeks" and no release-specific dates | [Sandbox Preview Instructions](https://help.salesforce.com/s/articleView?id=000391927&language=en_US&type=1), [Sandbox Preview unit](https://trailhead.salesforce.com/content/learn/modules/sf_releases/sf-releases-sandbox-preview) |
| Cutoff | Usually the day before the preview starts | [Sandbox Preview Instructions](https://help.salesforce.com/s/articleView?id=000391927&language=en_US&type=1) |
| Refresh after cutoff | Lands on a non-preview instance, current release | [Sandbox Preview Instructions](https://help.salesforce.com/s/articleView?id=000391927&language=en_US&type=1) |
| Request Non-Preview | Org permission from Customer Support; before the cutoff | [Sandbox Preview Instructions](https://help.salesforce.com/s/articleView?id=000391927&language=en_US&type=1) |
| Clones in the window | Same release as the sandbox being cloned | [Sandbox Preview Instructions](https://help.salesforce.com/s/articleView?id=000391927&language=en_US&type=1) |
| Checking placement | Release Type column on the production Sandboxes page, or the Sandbox Preview Guide | [Sandbox Preview Instructions](https://help.salesforce.com/s/articleView?id=000391927&language=en_US&type=1) |
| Release update test run | Enables the update immediately; sandbox test periods may end before Complete Steps By | [Release Updates](https://help.salesforce.com/s/articleView?language=en_US&id=sf.release_updates.htm&type=5) |
| Feature Impact filter | Enabled for Users finds Quick Wins; Admins must Enable finds Low-hanging Fruit | [New Features Enablement](https://trailhead.salesforce.com/content/learn/modules/sf_releases/sf_releases_strategy) |

## Check yourself

- Why must a sandbox refresh meant for the preview be requested well before the cutoff?
- When does a clone request land on the same release as its source sandbox?
- Where does an architect check whether each sandbox is preview or non-preview?
- Why run Low-hanging Fruit features past super users before rollout?

## Sources

- [Salesforce Sandbox Preview Instructions](https://help.salesforce.com/s/articleView?id=000391927&language=en_US&type=1)
- [Identify Which Sandboxes Get a Preview of the Next Salesforce Release](https://help.salesforce.com/s/articleView?language=en_US&id=release-notes.rn_sandboxes_early_upgrade.htm&type=5&release=240)
- [Release Updates](https://help.salesforce.com/s/articleView?language=en_US&id=sf.release_updates.htm&type=5)
- [New Features Enablement and Communication](https://trailhead.salesforce.com/content/learn/modules/sf_releases/sf_releases_strategy)
- [Get Early Access with the Sandbox Preview](https://trailhead.salesforce.com/content/learn/modules/sf_releases/sf-releases-sandbox-preview)
- [Get to Know the Salesforce Release Process](https://trailhead.salesforce.com/content/learn/modules/sf_releases/sf_releases_start)
- [Operational Excellence | Well-Architected Framework](https://architect.salesforce.com/docs/architect/well-architected/guide/operational-excellence.html)

## About the full unit

The "Core concepts", "Exam traps" and "Worked scenario" sections of this unit, its 9 linked practice questions, and unlimited timed mock exams are included with the Platform Development Lifecycle and Deployment Architect pack (USD $19): https://www.certifyforce.com/practice-exams