In the bag of poles that came with the^above^ trailer is a long extension pole that has a square cup on the end like the ones you use to support a square spreader bar. I cannot for the life of me work out what it is for as the trailer has the bare minimum poles for the awning setup and it is easy to workout where they all go except this one, it matches all the others in as far as it is the same brand and age so it looks like it came with the trailer so can any customline owners enlighten me as to what it is for or if isn't part of the normal setup at all? Tia.