<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by UnitedSkies:
Here are the "rules" as I understand them:
UA 1-1699 - mainline UA
* UA 1-99 Transcon/Premium Transcon
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Also mainland US - Hawaii flights fall in this range. There are occasional exceptions, like UA185 SFO-LIH.