That's quite a shame they had insufficient stock for the online launch. I think the goal of online shopping in advance was to avoid the retail hustle, but that's going to be the only way to get him. I know a lot of people will be disappointed, but he will be available more widely come September.
I'm so glad I bought mine at full retail though, rather than taking the risk for day of. They may well have more stock they're holding back for Thursday too.
On the lookout for MISB Headmaster Highbrow, Takara or Hasbro. I'm sure I could make you a sweet deal!