Got it, thanks guys! Does anyone have a sense of how much the cash upgrade offer from Y to J is? I am going to be flying one of the lowest demand frequencies / days of week, so I expect the upgrade to be available (I see 7 J and 7 F available on the day of for the same flight / day of week close in), but the cash fare for J is actually fairly reasonable as well for a lie flat, so I'm wondering whether I should just buy J to begin with or if Y + cash upgrade will be cheaper