My BITO Put Options got assigned

I’ve sold quite a few BITO (Proshares Bitcoin Strategy ETF) Put Options over the last few weeks. It is Friday, so some contracts will expire today. I just got home and logged into Interactive Brokers to Rollover my BITO November-19 55 Puts. I then realized that they got assigned already. This can happen anytime with US Style Options. In fact it’s actually a good thing for me that they got assigned, because now I’m holding BITO Shares. Interactive Brokers doesn’t allow retail Investors to buy BITO Shares, so selling “in the money” BITO Puts and letting them getting assigned is another way to go long in BITO Shares.