After attainment of the Father of spirits and admission to the seraphic service of completion, angels are sometimes assigned to the ministry of worlds settled in light and life. Large numbers of the completion seraphim return to their native universes, there to complement the ministry of divine endowment by the ministry of experiential perfection. 
Many fascinating avenues of ministry are open to the completion seraphim, but just as they all craved assignment as destiny guardians in the pre-Paradise days, so in the post-Paradise experience they most desire to serve as bestowal attendants of the incarnated Paradise Sons.  Often direct seraphic organizations. 
See also: UB 39:9.