Tubes getting hard to come by?

Hi All,

I've noticed that both Upscale Audio and the Tube Depot are running out of tubes, or, at least, they are limiting buyers to ONE TUBE PER MONTH (UPSCALE) or simply out of many popular tubes.  Am I imagining this, or is the pandemic, or something else, causing a dearth of available tubes?  Might this be a bad time to buy a tube amp because of this?