It is Yávië/Iavas...In Mirkwood.

Yep, that magical time of the year right before Quellë/Lasselanta (leaf-falling) in Mirkwood (and for all elves in middle earth)So, it’s important to have something for all the elves out there on the Yáviérë (Autumn Equinox). And it falls on Valanya (Valarsday/Friday)? Double the fun...

Legolas’ horse in Mirkwood is named Lasiavas (Autumn Leaf) just for the occasion.