For VCS, you can offline the IP resource, which will require offline of SQL and the Lanman resource and change the IP attribute to the new IP address. You could then online the IP resource, Lanman and SQL.
Since you are changing the node IP addresses, while the IP resouce is offline change the addresses at the operating system level, then online the IP resource, Lanman and SQL.
There is no need to start from the beginning and recongfiure everything. VCS does not need communicate with the other nodes in the cluster via IP. Make sure that the nodes can reach their Domain Controller via IP after you change the IP addresses. If you have other IPs in the cluster, for example in the CLusterService group, you may need to change these if the nodes have been changed to a different subnet.