You are given an `m x n` binary grid where `1` means infected and `0` means healthy, along with an integer `K`. The system evolves in discrete time steps. During each step, all updates happen simultaneously: - An infected cell stays infected. - A healthy cell becomes infected if and only if exactly `K` of its four orthogonal neighbors (`up`, `down`, `left`, `right`) are infected at the start of that step. - Neighbors outside the grid do not count. Write a function that returns the minimum number of time steps needed for all cells to become infected. If the process reaches a stable state and some cells are still healthy, return `-1`. You may assume the grid is non-empty.