• USD/JPY dropped from 158.85 in Jan to 139.89 in Apr

• Yen has soared during the trade war fuelling huge speculation

• Bets on yen rising have become enormous - last $14.5 billion

• 2025 low just short of target for a minor correction of longer-term uptrend

• A 38.2% retracement of 2020-2024 rise from 101.18 to 161.96 is 138.75

• Minor reverse of a major trend has led traders into an extreme position

• New strategies may be required to navigate changing FX landscape

(Jeremy Boulton is a Reuters market analyst. The views expressed are his own)