I suppose issues with powder will vary with conditions in the loading area. Damp, dry, or humid.
My area is dry and has good air circulation. As a result, I do not empty the powder all the time. If I am going to reload next day or two, I leave in. If more than that I empty back into same powder cannister.I do not mix batches or lots of powder, except when fininshing at the very end of a cannister. I then check throws and weights. As a habit though, I always check a few charges before I start anyway, for accuracy and consistency. When I use an adjustable bar, I check same after 100 or so rounds, as well as at thee end of lthe oading session. Usually always the same. One of the nicest things about the Star is consistent accuracy, a reason I like it!