Originally Posted by
mauiUAflyer
About the only thing you can try to do is contact your travel agent and then try to up-fare to a Y/B fare, or maybe even directly to a Z (discounted biz fare). No miles, swu, or cr1 will up fare you to y/b.
A SWU printed for LH use can be used to ugprade Y->C on a standby basis (one SWU per leg).
Otherwise, if the OP wants to use own miles, he/she needs to upfare to B first (keeping in mind that it's likely there will be no upgrade availability anyway).