Sounds like it saved you a lot of time getting your app up and running and I'm assuming they would give you a lot of time to migrate before just shutting it down. I wouldn't worry about this, however, this is something to consider any time you use a 3rd party to manage a service for you. I've had issues with fully managed RackSpace servers where the OS hit its EOL and it was on me to migrate everything to a new server. I've had this issue with fully managed database providers when they migrated to a new infrastructure and I had to move my data into a new database. There are other examples but most of them are pretty minor and none of them were too big of a deal.