Francisco Marmolejo pointed out a mistake in the statement of Proposition 4.4 in our TAC paper (Vol. 16, No. 28). The mistaken version is used later in that paper. Our purpose here is to correct the error by providing an explicit description of the finite coproduct completion of the dual of the category of connected G-sets. The description uses the distinguished morphisms of a factorization system on the category of G-sets.