Metalman
I understand you have not noticed any mechanical /noises the way the motor works.
Is this click after applying regen brake /after releasing brake lever/ still the same ? Or is it louder?
I would pay more attention to lubricate bearings if I rode in winter.
Bearings on EPLUS are high quality sealed Japanese ones just like on Tidal Force bikes, but I still lubricate them.
I place EPLUS on its side ,squirt 5 droplets of Mobil 1 motor oil to the centre of motor and next I rotate wheel to allow oil to flow down.
I do it on both sides of EPLUS.
High quality full synhetic Mobil 1 is one of the best if not the best motor oil in the world. It not just lubricate but also seals your EPLUS hub center from moisture penetration.
I know EPLUS motor stands out of many DD motors , because its mechanical design /example wires do not enter through axle like in your typical cheapo China brand but through individual holes in stainless steal solid centre hub/
but still few squirts of such fully synthetic oil from both sides keeps both sides centres oily - very good.