The GetCurrentContext response describes a single context.type field.  This limits it's use case to the "most recently opened anchor context", rather than representing all resources currently in context.  For applications that only synchronize for particular resources (i.e. Patient-level sync only), the GetCurrentContext request might result in a response with a resource they cannot understand despite there being relevant active context. 

Could we instead consider replaying events to the subscriber in response to a new subscription based on the events relevant to the new subscriber?  This would allow newly joining apps to catch up to the currently relevant context without having to submit an additional request and the context would be provided in a form they are signing up to process (via subscription).