Most, if not all, identity federations participating in eduGAIN manage users in an organization-centric fashion, which has several implications, like users changing organizations get issued new identities, even though they are linked to the very same person. An other case is that if no suitable primary affiliation exists (students leaving university or research collaboration with industry partners), there is no straight-forward way to get issued a valid identity at all.
In both cases, access to resources is lost, regardless of whether access rights were based on affiliation or on an individual basis.
Moving from an organization-centric identity management model to a user-centric model would do the trick, based on long-lived identity provider where the user is in control. Existing identity providers will become attribute providers serving information about the relationship with the individual. The long-lived identity provider will release basic information, combined with the additional attributes from the attribute providers.