The SD card (message history) could be lent to a computer from the lock
card before the PIN was entered. While locked with a PIN, usbPoll() no
longer reacts; a cable plugged in meanwhile is offered once unlocked.
The plain-text NVS PIN never shipped, so there's nothing to migrate.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>