Upgrade from 7.x to 8.+ series | Post 5 | Upgrade Sandbox and finally Production

Introduction

[EDIT]: Changes since November 2018 has forced me to made some changes to these series. I will point out the changes.

In these series of posts. I will try to run you through the process of how you can complete the upgrade from 7.x to 8.+ of Dynamics 365 for Finance and Operations.

Quick navigation:
Upgrade from 7.x to 8.+ series | Post 1 | Start in LCS
Upgrade from 7.x to 8.+ series | Post 2 | Deploy Dev and Grab source DB
Upgrade from 7.x to 8.+ series | Post 3 | Validate Code and Data in Dev

Upgrade from 7.x to 8.+ series | Post 4 | Setup a new Build
Upgrade from 7.x to 8.+ series | Post 4 | Upgrade Sandbox and finally Production (you are here)

Prepare a sandbox upgrade for validation

[EDIT]: This section has been modified.

Before you can go ahead and request an upgrade of Production, you will want to do a pre-production validation in the sandbox environment. You may read the details here:
https://docs.microsoft.com/en-us/dynamics365/unified-operations/dev-itpro/migration-upgrade/upgrade-latest-update#upgrade-your-tier2-standard-acceptance-test-sandbox-environment

Before you start this process, you will want to make sure you have the following uploaded to LCS Asset Library:

• Upgraded application ("Application deployable package"), downloaded or released from the successfull build
• The Update package ("Platform and application binary package") which you prepared on step 3 in the series, and installed on the build in step 4 of the series. 

You will service the sandbox and install the packages. If you're smart, you will merge the two packages into one single package, and service them together in one single operation. Merging package works as long as long as they are on same platform version.

Now you can let the users start hammering on the system to potentially discover everything is flawless (knock on wood).

If you do not have any Production deployed yet, the steps are:

1. Redeploy sandbox with target version. Make sure to select the upgraded application package. If you don't, you will have to install it afterwards, before you continue to the next step.
2. Import the upgraded bacpac from step 3 in the series. Here you can use the tooling in LCS if the database was uploaded into the Project Asset Library.
3. Validate!

Production

When you have validated the sandbox, and you are ready to upgrade Production, you will replay the steps you did in the sandbox, but this time in Production. 

Good luck!