For deme M, the population count was 586 until a change 9769.0 generations ago, where it increased to 2812, remaining steady thereafter.
time_units: generations
demes:
  - name: M
    start_time: .inf
    epochs:
      - start_size: 586
        end_time: 9769.0
      - start_size: 2812
        end_time: 0