Alan (as would be expected
) gave the answer. The precise policy is outlined on pages 8-101 through 8-102 of the Amtrack Service Standards Manual which can be downloaded
here. The variables are the accommodation charge you paid for the roomette (which bucket) and the low bucket price for the bedroom between the city pairs for which your upgrade is effective (often one or two stations downline -- or even more if it takes a while before the conductor deals with your upgrade) and the delta between the two numbers. In any event the minimum upgrade fee whould be $50 even if the calculation yields a lesser number.
I actually went through this process last year while riding the CS from LAUS to SEA. It was my first LD ride and although I was by myself I decided to splurge for the upgrade. The result of the calculations was $117 and I want to say that was based on the upgrade being effective somewhere north of Oxnard. If I recall correctly, the train was scheduledf for a two hour later than usual deparutre (~12:15 PM) from LAUS and no sooner was I situated then it was time to go to lunch. I think I inquired about the upgrade before lunch and my SCA (who may have even suggested the upgrade) and showed me the empty bedrooms. If I recall the sequence correctly he said we'd decide whether to do it after lunch and upon my return he moved me. But it was probably a good 30+ minutes before the conductor/assistant conductor actually came and took my money. I remember at the time being somewhat annoyed by how long this was taking but in retrospect they did me a favor because I want to say that the upgrade was from Santa Barbara. By suggesting we address the issue after lunch, the SCA saved me money.
I've since ridden the Silver Star (day only) in a roomette with my young daughter and although I remember last year on that LAUS-SEA initially being somewhat suprised and mildly disappointed at the roomette size (which is why I wanted to upgrade), I've since come to really like them.
Blue skies ..
BTW: For the truly cuious, the service manual says this:
Upgrade from Sleeping Car to Sleeping Car
The Conductor or Assistant Conductor must take
the following steps to upgrade a passenger from
Sleeping Car to Sleeping Car.
a) Check the manifest for available space.
b) If space is available, call (800) xxx-xxxx (the phone
number is also on the manifest) to hold the space.
c) Upgrade of Room Type for Entire Trip
• Determine the price the passenger paid for the
accommodation from their ticket.
• In the Conductor's Memorandum Tariff, go to the
page for fares specific to the train and city pairs.
• Using the D-Level accommodation charge for
the appropriate city pair and accommodation
type, determine the charge; then subtract the
accommodation charge that the passenger
already paid from that amount on their ticket.
• The difference is the amount to charge the
passenger for the upgrade.
• If this difference is under $50.00, charge
$50.00; it always costs a minimum of $50.00 to
upgrade to a higher room type.
• For Amtrak pass riders, apply both accommodation
charges to the 20% discount table.
• The minimum upgrade charge for an Amtrak
pass rider is still $50.00.
d) Upgrade of Room Type between Select City Pairs
• Determine the inventory class (S, A, B, C or D)
of the accommodation that was paid by the
passenger. This inventory class appears next to
the passenger's name on the manifest and is on
the passenger's ticket or ticket receipt.
• In the Conductor's Memorandum Tariff, go to
the page for fares between the city pair for
which the passenger wants to upgrade.
• Determine the D-level accommodation charge
of the higher priced room type between that
city pair.
• Using the D-level accommodation charge,
determine the charge for the lower priced
room type between that city pair – use the
accommodation charge that corresponds to the
inventory class originally paid by the passenger.
• Subtract the accommodation charge of the
lower room type from the higher priced.
• The difference is the amount to charge the
passenger for the upgrade.
• If this difference is under $50.00, charge
$50.00; it always costs a minimum of $50.00 to
upgrade to a higher room type.
• For Amtrak pass riders, apply both accommodation
charges to the 20% discount table.
• The minimum upgrade charge for an Amtrak
pass riders is still $50.00.
EXAMPLE:
A passenger has a ticket from Chicago to Seattle
showing the through "EB" roomette charge. At
Stanley, North Dakota, the passenger wants to
upgrade to an available unsold bedroom.
(Amounts shown are for the example only and
may not be accurate.)
• DD accommodation charge STN-SEA: $355.00.
• EB accommodation charge STN-SEA: $303.00.
• The charge to upgrade is $52.00.
8-102 Train Service Accounting Procedures
Service Standards Manual No. 6 8-103
If the passenger had paid the "EA" roomette charge:
• DD accommodation charge STN-SEA: $355.00.
• EA accommodation charge STN-SEA: $399.00.
• The difference is: ($44.00) (a negative number,
in this case).
• The difference is lower than the $50.00 minimum,
so the charge to upgrade would be $50.00.