AB Migration options for dual Ethernet networks

I will be upgrading a customer's existing Flexlogix system soon and their preference was to go to CompactLogix. It's a rather small program, so using a CLX would be overkill. However, there will be two remote racks that will be Ethernet. It is required to keep the PLC on the main network and the IO on a separate network, hence the dual Ethernet network requirement. I originally spec'd a 1768-L43 until I realized the firmware is capped at v20, and there is a campaign to bring everything to v24. I don't believe I have any other options at this point other than going to CLX. Am I forgetting something?

yes, you are forgetting that the new compactlogix line has two separate ethernet connectors that can be used as one DLR or with separate IP addresses.
http://ab.rockwellautomation.com/Programmable-Controllers/CompactLogix-5380-Controllers

Thank you!
I hadn't even looked at these yet.
F/W starting at v28 might be an issue for them. We'll see.
Thanks again.

yep, It has to be version 28.