Specialisation of LINE for flexible service. As all the service on a LINE may not all be flexible, flexibility itself is described at JOURNEY PATTERN level (meaning that a separate JOURNEY PATTERN is needed for each type of flexibility available for the line).<br/><br/>Types of flexible services are :<br/>- Virtual line service<br/>- Flexible service with main route<br/>- Corridor service <br/>- Fixed stop area-wide flexible service<br/>- Free area-wide flexible service<br/>- Mixed types of flexible service<br/>- Mixed type of flexible and regular services<br/>