I agree with UAPremExecflyer. Based on past experience, I chose to apply SWUs on this route for later in the year, but only when I saw NC availability so the SWUs cleared quickly. Ticket counter agent in ZRH told me that for westbound departures they often have no idea if upgrades will clear on not until very last minute at the gate, because many passengers are connecting on an interline basis from flights inbound from Africa. Some passengers may miss the flight at point of origin and others miss due to delayed arrival at ZRH. He also mentioned that these misconnects can then throw off the number for the following days for those of us trying to count seats and determine the likelihood of upgrades. Late last year I was waiting at the gate in ZRH, C was booked full, but there were four misconnects, so my upgrade cleared.