As noted, WWE NXT Women's Champion Asuka relinquished the title at tonight's TV tapings from Full Sail University, in a segment that should air on September 6th. We have full details from the segment at this link, including news on what's next for her.
WWE announced the following on The Empress of Tomorrow dropping the strap:
Asuka relinquishes NXT Women's Title
NXT Women's Champion Asuka relinquished her title to NXT General Manager William Regal tonight at Full Sail University in Orlando, Fla. After her dominant performance and historic 500-plus day reign as NXT Women's Champion, The Empress of Tomorrow looks to her future for new opportunities in WWE, though no specific details are known at this time. Her reign will officially end on the date that her historic announcement airs.
To see this monumental shift in the landscape of NXT, tune in each Wednesday to the award-winning WWE Network.