Mass as a function of effective temperature (left panel) and as a function of time (right panel). Stellar models that evolve towards effective temperatures below 27 000 K are affected by the bi-stability jump leading to an increase in the mass-loss rate. This is followed by a change in the slope of the mass as a function of time. The increase in mass-loss rate for rapidly rotating models is related to the change to the Hamann et al. (1995) mass-loss recipe.