The Tyger" is a poem by the English poet William Blake, published in 1794 as part of his Songs of Experience collection. It has been the subject of both literary criticism and many adaptations, including various musical versions.Literary critic Alfred Kazin calls it "the most famous of his poems",and The Cambridge Companion to William Blake says it is "the most anthologized poem in English".
In this scenario, yes, you should wait. If you know that there is a possibility that you won't even show up and that there will be extra seats anyways, there's absolutely no reason you should rush to buy the tickets and risk wasting money.