In other words, the B/A is determined by what "investors" are willing to pay. It takes UBSS about 30-90 minutes to enter my bid or offer since SPZI is unsolicited. (EDIT: unsless I pay the ask price or sell at the bid price) That is how I interpret it anyway. If I am mistaken, please inform me.
I had interesting experience the other day. I put a small buy order in at 0.012, except by mistake I submitted it as a sell. I was kicking myself. However it turned out that trade went through as a sell at 0.013. I was relieved and bought back the shares for the same price - I was only out the commission.
Not sure why it happened, but I didn't complain on that occasion.