Does the Earth's rotation speed really tend to accelerate for a long time?

Recently published studies suggested that the difference between Universal and Coordinated Time UT1-UTC could reach a large positive value in a few years, making it necessary to introduce a negative leap second into the UTC scale for the first time in its history. Based on the latest UT1 series provided by the International Earth Rotation and Reference Systems Service (IERS) and its prediction, it was shown that the tendency to acceleration of the Earth's rotation observed over past four years most likely will return to the deceleration, which is the usual behavior of the Earth rotational dynamics.