I already have a uAvionix Tail Beacon

Note that the uAvionix Tail Beacon is a Position light only, with no strobe function.
To complete the lighting requirements for night flight you need a tail strobe as well, such as our standard kit model tail light.

Many customers have simply moved their Tail Beacon into a wingtip instead, where it can still happily maintain your ADSB-Out requirements, leaving room for our tail light on the rudder.