LPC17xx and FreeRTOS-TCP NetworkInterface.c

I am looking at reworking an old project that uses the LPC1768 and am currently trying to work out whether FreeRTOS-TCP would be the better option than just updating the old version of lwIP that was used previously. I have created a dummy project and am trying to compile the network driver under FreeRTOS v10.1.0 from Source/FreeRTOS-Plus-TCP/portable/NetworkInterface/LPC17xx. I have fixed a couple of issues where the pucBuffer field in the NetworkBufferDescriptort appears to have changed name to pucEthernetBuffer and it seemed to prefer xIPStackEventt instead of IPStackEvent_t. I have warning from the compiler (gcc 7.3.1) that the external variable xNetworkEventQueue isn’t used anywhere in the NetworkInterface.c file (which is correct) – in which case, how are Ethernet events communicated to the IP task as the comment suggests? Has anyone already fixed this driver and got it working with a recent version of FreeRTOS-TCP and can share their work? Also, I see no evidence in the code of the PHY being initialised anywhere. Thanks, -Andy.