Up until 5585.666 generations ago, the count of F deme was 3296. Following that period, it reduced to 357, where it has persisted until now.
time_units: generations
demes:
  - name: F
    start_time: .inf
    epochs:
      - start_size: 3296
        end_time: 5585.666
      - start_size: 357
        end_time: 0