A method performed by a first infrastructure equipment acting as a source for forwarding data received by the first infrastructure equipment to a second infrastructure equipment acting as a target for a wireless communications device during handover, the method comprising: receiving data for transmission to the wireless communications device from a core network to which the first infrastructure equipment is connected, generating a message for transmission to the wireless communications device, the message including the received data, a first protocol header according to a first protocol and a second protocol header according to a second protocol, determining a sequence number in accordance with the second protocol, determining that the wireless communications device has performed the handover, and in response to determining that the wireless communications device has performed the handover, removing the second protocol header from the message, transmitting the sequence number determined in accordance with the second protocol to the second infrastructure equipment, the second infrastructure equipment being connected to a second core network different from the first core network, and either transmitting the message including the received data and the first protocol header to the second infrastructure equipment for transmission to the wireless communications device, or removing the first protocol header from the message and transmitting the message including the received data to the second infrastructure equipment for transmission to the wireless communications device, wherein the first protocol provides a mapping of a plurality of packet bearers, configured to provide a specified quality of service, to a data radio bearer. receiving data for transmission to the wireless communications device from a core network to which the first infrastructure equipment is connected, generating a message for transmission to the wireless communications device, the message including the received data, a first protocol header according to a first protocol and a second protocol header according to a second protocol, determining a sequence number in accordance with the second protocol, determining that the wireless communications device has performed the handover, and in response to determining that the wireless communications device has performed the handover, removing the second protocol header from the message, transmitting the sequence number determined in accordance with the second protocol to the second infrastructure equipment, the second infrastructure equipment being connected to a second core network different from the first core network, and either transmitting the message including the received data and the first protocol header to the second infrastructure equipment for transmission to the wireless communications device, or removing the first protocol header from the message and transmitting the message including the received data to the second infrastructure equipment for transmission to the wireless communications device, wherein the first protocol provides a mapping of a plurality of packet bearers, configured to provide a specified quality of service, to a data radio bearer.