A method implemented at a terminal device , the method comprising: receiving Cell Broadcast Service, CBS, messages from a network device in a receiving time interval of a first Discontinuous Reception, DRX, period , the first DRX period including at least said receiving time interval and a dormant time interval without receipt of CBS messages; characterised by : detecting whether there is a change among the CBS messages received in the receiving time interval of the first DRX period ; and when a change among said CBS messages is detected, determining a configuration of a second DRX period , the second DRX period including at least a dormant time interval , which occurs after the receiving time interval of the first DRX period , and a receiving time interval for receiving further CBS messages, wherein the determining the configuration of the second DRX period comprises: in response to detecting a change among said CBS messages , setting a time length for the dormant time interval of the second DRX period below a dormant threshold and, in response to determining that said CBS messages remain unchanged, setting the time length for the dormant time interval of the second DRX period above the dormant threshold; and in response to detecting a change among said CBS messages , setting a time length for the receiving time interval of the second DRX period above a receiving threshold and, in response to determining that said CBS messages remain unchanged, setting the time length for the receiving time interval of the second DRX period below the receiving threshold. detecting whether there is a change among the CBS messages received in the receiving time interval of the first DRX period ; and when a change among said CBS messages is detected, determining a configuration of a second DRX period , the second DRX period including at least a dormant time interval , which occurs after the receiving time interval of the first DRX period , and a receiving time interval for receiving further CBS messages, wherein the determining the configuration of the second DRX period comprises: in response to detecting a change among said CBS messages , setting a time length for the dormant time interval of the second DRX period below a dormant threshold and, in response to determining that said CBS messages remain unchanged, setting the time length for the dormant time interval of the second DRX period above the dormant threshold; and in response to detecting a change among said CBS messages , setting a time length for the receiving time interval of the second DRX period above a receiving threshold and, in response to determining that said CBS messages remain unchanged, setting the time length for the receiving time interval of the second DRX period below the receiving threshold. in response to detecting a change among said CBS messages , setting a time length for the dormant time interval of the second DRX period below a dormant threshold and, in response to determining that said CBS messages remain unchanged, setting the time length for the dormant time interval of the second DRX period above the dormant threshold; and in response to detecting a change among said CBS messages , setting a time length for the receiving time interval of the second DRX period above a receiving threshold and, in response to determining that said CBS messages remain unchanged, setting the time length for the receiving time interval of the second DRX period below the receiving threshold. <EOS>