At Monday 30 Ukraine and Russian media reported about a request by president Poroshenko to the Ukraine parliament requesting to prolong the JIT agreement to August 1, 2018. Interfax has an article in english language here.
The request to adjust the law/agreement can be seen here.
The current agreement, which expiration date was extended severall times, currently expires in January 2018.
In January 2016 the agreement was prolonged to October 2016.
Earlier in a letter to the Dutch parliament Dutch government suggested an extension of the JIT agreement.
Extension means JIT needs more time to find names of suspects, or to find a motive, or to prepare a case for a court.