The GBPUSD pushed to a new session high of 1.3770, briefly surpassing both the earlier high at 1.3764 and the 50% retracement of the decline from the 2014 high, which comes in at 1.37683. However, the break above these levels was shallow and lacked follow-through, raising concerns that momentum may be fading.From a technical perspective, failing to hold above the 50% midpoint and prior highs is a potential red flag for buyers. A reversal below these zones could prompt profit-taking or invite sellers back into the market.For sellers to gain more confidence, a few key levels need to give way:Staying below 1.3770 keeps the top in placeBreaking below 1.3697 (recent swing lows on the hourly chart) would strengthen the bearish caseA move under 1.3647 and 1.3631 (highs from yesterday and June 14) would be further confirmationUltimately, falling below the rising 100-hour moving average at 1.3582 would shift the short-term bias more clearly in favor of sellersFor now, while the pair isn't collapsing, the lack of conviction at new highs could make bulls cautious and give bears something to lean on. This article was written by Greg Michalowski at www.forexlive.com.