RPi4 boot order from USB

  • I've just downloaded the latest nightly, burnt a clean SSD to try things out and so far I'm impressed. I did have a slightly weird thing happen. Normally I've been plugging the boot SSD into the bottom USB3 port. This time I plugged it into the top one and a 600GB spinner (I'll swop to my 6TB after I've tested for a while) into the bottom. I was asked to choose an OS and the RPi4 was going on-line to download my selection.

    Is there a specific order that the Pi looks for bootable media in and does it just stop looking as soon as it finds a drive connected OS installed or not? On the other hand is it just something weird I must have done?