Forum:Evilswarm thunderbird

 A friend was in a tournament in a local store and his opponent used the effect of evilswarm thunderbird in his turn, but forgot to return it in my friend's stand by phase, and in his stand by phase he wants to return his evilswarm to his side of the field, is that posible? Ot the thunderbird will reamin banished because he forgot to special summon it when he should?