Amsterdam Airport Schiphol aims to have a fully autonomous taxibot fleet that can taxi all incoming and outgoing flights by 2050. To support the transition towards this future state, wherein the demand for taxibots will initially be higher than the supply and operational concepts will continuously evolve, a flexible taxibot allocation model is developed. This model can optimize for different objectives: fuel savings, schedule robustness in terms of flight delays, a healthy working environment, and fairness towards participating airlines. The model is proven to be versatile and applicable to many phases towards the 2050 vision. However, this also makes the model computationally complex, which should be investigated in further research.