Thanks for the point! In this case I meant more the situation that the same service (single service, single DB) might be running with more than one version concurrently (during a rolling deployment, or a canary deployment etc) which can lead to issues. The other case is that if services depend on an old contract there could be times where teams might run multiple versions of a service to allow different APIs to be used, rather than a single version of the service which exposes all current compatible APIs. Although to be honest, this is an issue with any service.
Thanks for the point! In this case I meant more the situation that the same service (single service, single DB) might be running with more than one version concurrently (during a rolling deployment, or a canary deployment etc) which can lead to issues. The other case is that if services depend on an old contract there could be times where teams might run multiple versions of a service to allow different APIs to be used, rather than a single version of the service which exposes all current compatible APIs. Although to be honest, this is an issue with any service.