Later this week I will be arriving into CUS on the Capitol Limited on sleeper and transferring to the Illini, on which I am now ticketed for coach. I am hoping I can take advantage of an upgrade coupon to Business Class, though I have to call in no earlier than 12 hours before departure to apply that which means about 5 a.m. when AGR lines open. If it is booked and I am unable to use the upgrade, I know I have liberty to use the Metropolitan Lounge given my sleeper ticket on the inbound CL, but am I correct in my presumption I will be permitted to board early from the lounge along with Business Class? Appreciate in advance any insight.