Strapi V3 to V4 migration on Heroku

Did anyone manage to do a full v3 to v4 migration on a Heroku-hosted Strapi?

If you did manage, how was it? Did you use any migration scripts for the database, or did you do everything manually?

We are about to pull the trigger on a v3 to v4 migration on Heroku. I ended up using the migration tool with a handful of custom migration scripts. It’s all working well locally. Currently coming up with the game plan for doing this on Heroku. Would be happy to post here once it’s done with any lessons learned. Did you end up doing the migration already? If so, how’d it go?