The rapid growth of rooftop solar, and on the rise technologies such as electric vehicles and heat pumps, is leading to congestion problems in low voltage distribution networks. If not dealt with, the congestion will prevent the installation of further units limiting the pace of the energy transition. Energy Storage Systems (ESS) are often seen as the technology with a high potential for congestion reduction. In this paper, we propose to use Relocatable Energy Storage System (RESS) fleet, to physically move the ESS throughout the distribution grid in an effort to alleviate congestion. The proposed method consists of two parts. First, a Mixed Integer Linear Program (MILP) is created to minimise the amount of RESS used and penalise displacement. Second, an algorithm with a Minimum Cost Maximum Matching objective is used to determine the dispatch of each individual RESS. The results on a CIGRE test system show the benefits of this method compared to stationary placed ESS in the grid.