Yes, a former seconded national expert can work as a temporary agent or a contract agent, provided that they still have time to go before they reach the six-year limit (the maximum allowed stay in the Commission on any combination of non-permanent contracts is six years).
And of course they must be eligible for a contract agent position (i.e. they must have passed the selection procedure and be in the CAST database).
Temporary agent contracts at the moment are very very difficult to obtain.
© 1962-2020 The Bulletin