Amston Lake / Alder Lake-N (Atom x7433RE) with IgH EtherCAT — kernel version exp

Hello all,I'm specifying the controller for LinuxCNC as EtherCAT master via IgH/EtherLab, CiA 402 servo drives, 1 kHz servo loop.. Two industrial box PCs are shortlisted, both built on Intel Atom x7433RE (Amston Lake / Alder Lake-N):

• ASRock Industrial iEP-5020G — 2 × i210-IT + 1 × i226-IT
• IBASE AGS104T — 2 × i226-IT

One of the vendors has just told me that Intel specifies kernel 6.18 or later for the Amston Lake platform, and points at Intel's RT kernel overlay (linux-image-6.18rt-intel) which targets Ubuntu. Debian 13 ships 6.12, and as far as I can tell so does the LinuxCNC Debian 13 PREEMPT_RT ISO. Before I commit to hardware I'd rather learn from people who've actually done this than find out on the bench.Questions:

1. Is anyone running LinuxCNC + IgH EtherCAT on Amston Lake or Alder Lake-N (x7433RE, x7835RE, N97, N100, N150)? Which distro and kernel?
2. Does the "6.18 or later" requirement actually bite on a 6.12 RT kernel, or is the gap mainly graphics/TCC/TSN enablement rather than boot, Ethernet and serial? I'd expect the i210/i226 drivers to be long-since mainline, but I don't want to assume.
3. IgH native NIC drivers vs generic — On a recent kernel, do ec_igb / ec_e1000e still build, or are people falling back to the generic driver? If generic, what did it cost in worst-case jitter?
4. i210-IT vs i226-IT for the master port. I've seen the i210 preferred here for worst-case timing. With both available on the same box, is that still the recommendation, or has the i226 situation improved?
5. Real latency numbers welcome — latency-histogram max on the servo thread, under load, at 1 kHz, on any Alder Lake-N class machine.
6. If you did run a newer RT kernel on Debian, did you build it yourself or use a repo, and did anything in the LinuxCNC/IgH build need patching?

I'll post my own results back here once hardware is on the bench — latency histograms, IgH timing, and whatever I learn about the kernel question — in case it's useful to the next person choosing one of these boxes.

I'll be honest, AI is helping me build this machine. I am not as knowledgeable as this post makes me seem - but please dont hold that against me.  I really would like some assistance rather than spending hours on a new machine only to find out it won't work for me.