Yobit.io??, I guess you accessed a fake website, the real yobit is yobit.net.
I checked both the sites now and io one is a fake one , be careful out there.
No according to yobit's twitter account yobit.io is its backup domain. It's legit.
https://twitter.com/yobitexchange/status/793036105486663680Regarding the OPs delayed transaction someone made a post explaining that the ethereum network is so overloaded that all the exchanges are having problems with transactions. He posted this image to make his point.

Yobit should have at least answered his support ticket by now, but they are probably snowed under with them.