The script lettering at the very top introduces an ad campaign created in 1907. When newly painted, it's likely that this sign read, in full ...
Eventually
Washburn-
Crosby's
Gold
Medal
Flour
Why not now?
Gold Medal, whose roots reach back to the mid-19th century, used this ad campaign as late as the 1950s, so the sign is at least six decades old. Eventually it will vanish entirely, but not just now.
Gold Medal Flour
Surviving signage near the northeast corner of Delancey and Eldridge Sts., Manhattan