@Derelict @jimp thanks for that feedback. I'll will try as you suggest and report back.
I had another conversation with a friend last night and came up with 3 other possible solutions as well.
Ask the ISP for addresses in the same block with the same gateway(preferably in our original address space). I asked this yesterday day and waiting for a response. This is as @Derelict said.
If the above isn't possible, can they tag the new gateway and I could at a vlan sub interface on the wan. Not sure this is possible in pfsense as I haven't had time to investigate.
Add a dumb switch in front of my firewall and split their connection into 2 connections and use another interface on my box for the new gateway and ip's.
While senerio 1 is the most desirable, anyone see problems with 2 or 3?
We've had our public IP for over 10 years and while I could just get a block of them all together we would like to keep our existing.
That being said since our existing is a 173 in a 24 block and the new ones are 208 in a 24 block is oblivious that our ISP is trying to conserve IP's by using 24's and not splitting the blocks up into smaller 28,29 or 30's. Why make 30'and limit the customers they can handle to 64 instead of 254... So I'm thinking or primary IP block is probably full which makes me think I'll be looking to solution 2, 3 or the above as jimp stated.
And the no particular reason we would like to keep our existing IP, other than we've had it a long time...