The Advance Block is a three-candle bearish reversal pattern that forms during an uptrend, consisting of three consecutive bullish candles where each candle's body is progressively smaller, the upper wicks are increasingly long, and each candle opens within the previous candle's body. Unlike the Three White Soldiers pattern—which signals a healthy, accelerating uptrend the Advance Block suggests that buying momentum is deteriorating even as prices continue to rise. The shrinking bodies and lengthening upper wicks indicate that sellers are increasingly challenging buyers near the highs. It is a warning sign of a possible reversal or at least a pause in the uptrend, and is most significant when it appears near a known resistance level or after an extended rally.