I think a lot of investors have sold pre ex date to fund options. (I know quite a few investors and almost all of them have) The equivolume has been down quite a bit last few sessions so I suspect that there isn't a lot of retail selling. (some market maker churn)
Having been through these scenarios before, I would expect that a large percentage of investors selling post the ex date have already done so. I don't expect a lot of selling post issue - remembering that there is the 1:15 ratio of oppie to heads. I suggest that investors do speak with their broker/advisor if they don't understand the maths, tax implications, etc... IHL also has a habit of trending very nicely after options series. History tends to repeat.