I opened a support case. The went through the config and agreed it was fine.
Tarinelli, I think your correct it is not a firewall issue.
The thing was that when the printers lost connectivity they were not in the user table at all.
Anyway, at this point I'm looking at the printers going into power save mode as the problem. When they do this they leave the user table all together and thus the user rule allowing access to them is not active. Then new jobs from the print server can't reach them to 'wake' them back up.
I've removed or adjusted the hybernating settings on the printers and so far they are staying in the user-table.
I'm not sure what I'll do long term for this. These printers are leased and managed by a printer/copier distributer and I'm thinking they will want their printers to hybernate when not in use.
Any thought on a work around for this?
Thanks for the responses so far.
Michael