Free gauntlet banner without being on lb

[Arrowz]

So when gauntlet 2 came out i was planning to run it but I was busy that week and only ended up doing 23 runs for a total of 230 points, not nearly enough to make the lb. A couple weeks later i checked my stash and there it was, a free gauntlet banner lol. Anybody have any explanation for this? Heres some pictures to prove i only ran it 23 times but still got the banner.