I suppose I could email them but thought I'd ask here first.
When they put 25 MHz back OTA a short while back I sent them an email report and received the current QSL. It's pretty nice. There are separate cards for each station, ie, WWV vs, WWVH, WWVB etc. You can see them displayed and get the email address on their web site,https://www.nist.gov/time-and-frequency-services/nist-radio-stations/wwv
Their 25 MHz transmitter had / has a modulation spur issue. Whenever it was at least S9 or louder here, when the solar index info or other voice bulletin is spoken (with greater modulation then the time announcer) the modulation splatter can be clearly heard +/- (mostly plus) about 15 Khz from the fundamental.
I had some correspondence with them about that and after using a spectrum analyzer they confirmed there was a problem, but the spurious emission power was so low (like < -50db) they were amazed that I heard it. And as such it sounded like they didn't care much to fix it either, lol!