When non-revving on US, it's easiest to just get a Y class zed and purchase an upgrade coupon at the airport if F is available when they are about to clear the list. It's $20 for North America, the Caribbean, and Central America. Transatlantic is $100. Domestic upgrades are non-refundable, but transatlantic is refundable. Both are transferrable. You will occasionally find some agents who will just clear you to F or C, but they aren't terribly common.
It's not too common to get F on domestic routes, except maybe the shuttle or some off-peak hub flights. You never know, though! Don't be ashamed to ask.[/b]
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