Comment 5 for bug 237460

What needs to be done to make the open-iscsi-udeb load earlier in the install sequence so its block devices are available to disk-detect?

Sounds like the initramfs problem is solved.

As for blowing away the networking, one possible solution: if the installer knows what interface the initiator came up on, it can set that to "manual" in /etc/network/interfaces as part of its cleanup.