Site was slammed starting a few minutes before the drop. When it finally updated, it showed 26 or 27 in stock (PCB w/ cartridge shell). Over the next 15 minutes, it insisted there was insufficient stock - "Sorry, insufficient stock for item pitrexV1GTcase" - for any order I tried to add to my cart, while that number eventually dwindled down to zero. I'm assuming the site just can't handle the volume of requests, and it wasn't updating the availability perhaps? Very odd...
I expect they could easily sell a couple hundred of these in a day or two, so surprised the number available was so low? Not sure how often stock is replenished, but will keep trying!
I didn't otherwise see any obvious link on the PiTrex page for getting an email notification?