Evolution of the eclipse duration at pericentre for the simulation models. The hashed blue region indicates the observed duration of 56 ± 4 days, while the hashed turquoise region indicates the observed velocity of 32 ± 2 km s^-1. The upper models with the longer eclipse duration are the retrograde models, the lower models are the prograde ones. The colour bar indicates the age of the model in log ₁₀-scale: lightest is after 3000 yr, while darkest is after 10⁵ yr.