@cosmowave Thanks, I've updated the documentation here: https://docs.duet3d.com/en/User_manual/Connecting_hardware/IO_Neopixel_DotStar#neopixel-leds
Multiple LED strips are supported:
Duet 3: up to 5 in a system (mainboard + expansion boards) Duet 2 WiFi/Ethernet: up to 2 LED strips, limited by RAM
It's possible that @dc42 might be able to increase the number of LED strips supported in the next release, particularly if you're only using a small number of LEDs on each strip. But it will depend how much free RAM you have on the Duet, as space is rather limited on Duet 2.
Ian