I have written multiple times about GPUs and RPUs in this forum. First of all, United provides these instruments as a result of miles flown by elite members. They are not "free" with respect to United deciding to "give them away". We pay for these multiple times over with our paid tickets. Second, I have also been frustrated with a completely empty business class cabin and no confirmable upgrades months in advance for off-peak travel (London Heathrow from Chicago in February, mid-week). I do not agree that there should not be some confirmable space for upgrades on these flights months ahead. However, that said, I just booked a confirmed GPU on this route two days ago because I checked multiple times weekly about availability since June, 2017. Usually weekend days are the best chance to secure a confirmed upgrade, but I have also had lots of success in the past during the weeks between Thanksgiving and Christmas, which is how I was able to confirm the ORD-LHR GPUs.