Double M freeze branded their heifers in November. They wait until then, because we only freeze brand the heifers that we'll keep as replacements.
Freeze branding is really nice, because it creates a second way to identify a cow. At Double M, all of the cows are tagged in their left ear, and then freeze branded on their right hip. So no matter what side of the cow you're on, you can identify her number.
This is especially important at 2:00 am on a cold January morning when you're trying to figure out the cow who's just calved, light is minimal, you're exhausted, it's cold outside and the dang cow won't stand still long enough for your to read her ear tag.
So yes - the day (or sometimes 2 days, depending on what else is going on that day) it takes to freeze brand are well worth it.