Couchbase server migraion 6-->7

Hi All,
our client needs to move from 6 to 7 version. He run Cb in K8. I’ve two questions:

  1. our dev env is on windows. Is it possible to upgrade the server on-place? Or we need to backup the data, uninstall and reinstall, and restore the data?

  2. Our client use Sync Gateway and the Sync Gateway Replicas between an edge cluster and a central cluster. They plan to install the new clusters and transfer the data between old and new cluster with XDCR. I expect to shout down the SG services, to transfer the data and then to start the new SG services. So I expect that XDCR will transfer also the SG specific documents toward the new cluster. Is there any criticalities with this approach? I mean, once the new SG start, then it will create its index and so on.