Not lately. I see
Retumbo on the Hodgdon site about once a month. Powder Valley still has some of the best prices, but they have no notification system so you just have to check it multiple times a day and hope that you catch it at the right time. In lieu of that, as much as I hate to pay Larry's higher prices, MidwayUSA has been the easiest way to get most powder because they'll actually notify you when stuff is in stock. Midsouth Shooter Supply also has meh prices but is good on notifications. Brownells seems to get a similar volume as Midway, but I never get notifications from them. Grafs is good on notifications, but low on volume.
So my suggestion is to put in notifications for the powder you need on Midway and Midsouth and just check your email often and cross your fingers. I'm working from home and on a computer all day, so it's also easy for me to check regularly. When rarities like N570 and primers show up, I post here.