Until a shift occurred 1957.9 generations ago, deme L's population was consistently 6537. Since then, it changed to 8528, a number that has remained unchanged to the current time.
time_units: generations
demes:
  - name: L
    start_time: .inf
    epochs:
      - start_size: 6537
        end_time: 1957.9
      - start_size: 8528
        end_time: 0