general post
/ˌdʒɛn(ə)rəl ˈpəʊst/ /ˌdʒɛn(ə)r(ə)l ˈpəʊst/noun
1A game in which each player is called by the name of a place to which letters are supposed to be sent and all are required to change seats when ‘general post’ is called.
2 Figurative. A general and rapid exchange or interchange of positions, etc.
Origin
Late 17th century (in an earlier sense). From general + post.