The Google store was extremely slow during this period. I tried to initiate a purchase around 5 minutes after they became available, but 95% of my clicks resulted in errors, and when it finally went through, the Wallet info collector hung for another 5 minutes. When that finally went through, my cart had had the phone removed from it, and they were once again out of stock.
So the 50 minutes is probably somewhat inflated. Had the store kept pace it probably would've been more like 10 minutes.