A few days ago, I received an email from Heroku for upgrading Redis 6.2.14 to 7.2 due to a deprecated issue.

And to follow up on this warning, I asked my client to upgrade the Redis version. Once approved, here are my steps to upgrade Redis:

I used heroku CLI for upgrading Redis.

Login to Heroku

heroku login

Show all apps on Heroku

heroku apps

Show current Redis version

heroku redis:info -a <APP_NAME>

Replace <APP_NAME> by your real app name.

Perform or schedule the upgrade using

heroku redis:upgrade <REDIS_NAME> --version <VERSION> -a <APP_NAME>

Replace <REDIS_NAME> by your Redis instance name, use the name from the heroku redis:info result.
replace <VERSION> by Redis's target version.

Example:

redis:upgrade redis-octagonal-30151 --version 7.2 -a super-app

You can check again using heroku redis:info to know when the upgrade would be performed by heroku.