Southern States makes my TC feed and if they have a winter formula, it sure doesn’t help! During the cooler months I find that Complete, Senior, and Growth all tend to be bricks. It drives me nuts!! I drop bags on the floor before opening them then I have what is essentially an ice pick that I use to break up clumps…
Even during warmer months there will be bags that tend to ‘hold their shape’ and have big hard-to-break clumps when they’re dumped. I just deal with it <sigh>