For the first time this year (since January) in my many years as a 1K, I have been unable to confirm a business class seat upgrade at the time of ticket purchase using a SWU. On two recent round-trips to Europe, which I'm trying to book for April and May, the 1K agent checked every transatlantic flight and connection possibility for a two-week window on each side of my departure and return dates. She told me that all of the business class cabins were "wide open", but there were no confirmable upgrades on any flights across the atlantic for as "far out" as she checked. She told me that upgrades were available with Star Alliance partners, but they would not accept the SWU. I contacted the 1K voice, and was told matter-of-factly that this is the policy--those seats are for purchase, and their upgrade policy was "fair".
Have others had these experiences? Are the SWUs just going to be "buy your ticket and wait until the departure gate?" As recently as last Fall, I was able to use my SWUs with confirmed upgrades, as long as I was flexible with time of day or within a two-day range. Is this the result of the DEQM promotions with so many 1Ks, or does everyone just go into a big list and it gets sorted out at flight time?
I have noticed exactly the same set of issues although in my case I was trying to book upgraded flights the week of Oct 1 or 2 thru Oct 8th to London. This has historically been a good time for obtaining upgrades but nothing is currently available during that time frame. Saver business class seats are available but no SWU upgradable seats. My strategy now is to simply purchase a fully refundable fare with the hope of finding a set of flights with upgradable seats as we get closer to departure day. If that doesn't work there is always the option of a Z fare on a different Star Alliance carrier - often times other Star Alliance carriers allow a Z fare without requiring a 7 day stay which UAL often requires for discounted Z fares. Sometimes the advance purchase window on other carriers is less than UALs norm of 50 days. In almost all cases their fares are the same or less expensive.
The final option is to simply book a backup set of flights using a saver award - that is what I will do for the October trip. If I don't get upgraded in advance, I will simply cancel the B fare and use miles. I will always be at the 1K level and I have more miles than I care to admit. I fully expect UA to disappear before I ever get around to spending those miles.
The lack of upgrades has encouraged me to purchase less expensive Z class fares on other airlines. I expect that I may end up losing at least 7 or 8 SWUs this year because of expiration dates.