After thinking back on it, I think this was earlyish October. The code hadn't frozen yet, but it was getting increasingly difficult. We were in the "this was deployed to about 1/3 of the stores - all within an 8 drive of the general office". The go/no-go decision for the rest of the stores in October was coming up (and people were reviewing backout procedures for those 100). One of the awkward parts was that marketing had a Black Friday sale that they really wanted to do (buy X, buy Y, get Z half price) that the old registers couldn't support. They wanted to get a "is this going?" so they could start printing the advertising flyers.

Incidentally, this bug resurfaced for the next five years in a different incarnation. Because it had that this department (it was with one sku) had sold $10M this week in October, the running average sales target the next year was MEAN($24k, $25k, $26k, $25k, $10M) ... and the department heads were doing a "you want me to sell how much?!"

This bug had only affected... maybe five stores (still maybe five too many). We were in the "this is the last™ build before all store deployment next week" territory. It did mess with that a bit too as the boxed up registers came with an additional step of "make sure to reboot the register after doing initial confirmation."

The setup teams had a pallet of computers delivered to the stores that were supposed to be "remove the old registers, put these registers in, swap mag strip readers, take that laptop there and run this software to configure the devices on each register." However, the build that the registers had was the buggy build. While that build likely wouldn't hit that bug (it required a particular sale to be active which was only at a few stores and had ended) it still was another step that they had to follow.

Aside: For all its clunkiness, Java Web Start was neat. In particular, it meant that instead of trying to push software to 5k registers (how do you push to registers that are powered off?), instead we'd push to 300 stores and from there JWS would check for an update each time it started up ( https://docs.oracle.com/javase/8/docs/technotes/guides/javaw... ). So instead of pushing to 5k registers, we'd have it pull from 'posupdate' on the local network when it rebooted.