Modelling railway curve squeal poses a challenge since the phenomenon is non-linear, transient and complex. This work focusses on the transient effects of varying contact parameters on curve squeal. A previously developed high-frequency tool for the simulation of curve squeal in the time domain during quasi-static curving is extended to account for transient curving and connected to a software for the low-frequency vehicle dynamics. An application of the model demonstrates that time-varying contact parameters such as contact position, lateral creepage, and friction coefficient can lead to an on- and offset of squeal. The history of the wheel/rail dynamics can also have an influence on the occurrence of squeal and the selection of the squeal frequency.