Yes. Apps created using Open Liberty can easily be migrated to any version of WebSphere Liberty because the WebSphere Liberty portfolio is built on top of Open Liberty. The codebase of the commercial portfolio includes 100% of the Open Liberty code. They share the same code, but WebSphere Liberty has additional features that are not open source.
Apps created using Open Liberty can be migrated to WebSphere Base and Network Deployment, but there are a few differences to consider, just as when moving from WebSphere Liberty to traditional WebSphere. Open Liberty provides an implementation of Java EE 8, which is also available in WebSphere Liberty and traditional WebSphere, that makes the migration of apps that use these features easy. Open Liberty also provides an implementation of the Eclipse MicroProfile capabilities for building Java microservices. Eclipse MicroProfile capabilities are available in WebSphere Liberty, but not on traditional WebSphere. Apps that use these features are not as easily migrated from Open Liberty to traditional WebSphere. \r