A User equipment (UE) transmits, to a base station, a capability information indicating whether the UE supports UE-based timing advance measurement, and receives, from the base station, an indication indicating whether UE-based timing advance measurement is enabled for a candidate cell for layer 1/layer 2 triggered mobility (LTM). The UE configures UE-based timing advance measurement for the candidate cell for LTM based on the indication, and performs UE-based timing advance measurement for the candidate cell for LTM. The UE receives a cell switch command from the base station. When a valid timing advance is not included in the cell switch command, the UE switches to the candidate cell for LTM by applying a timing advance measured by the UE. When the valid timing advance is included in the cell switch command, the UE switches to the candidate cell for LTM by applying the valid timing advance.