Oxford
Chillin' In The Garden
I had a similar experience. Succotash is a late-flowering bean, but I ended up harvesting a lot of nice seeds.
I also heard that it is late-flowering. However, they are always mid-late flowering in my garden and I have already some small pods.
I have varieties that bloom much later, such as the blue-white of Bernarda, Schwarze Kugelbohne (literally translated as Black Ball Bean), San Michele Rosso, and the Tuvagliedda Marrone and Tuvagliedda Rossa.