** JPMorgan upgrade to "overweight" vs "neutral" sendsfashion retailer Next to the top of the FTSE 100
** While broker still favours M&S on a 3-6 mth viewfor ongoing turnaround potential, reckons NXT could recover someof its recent underperformance between now & end-April Q1 update
** JPM says recent beneficial weather & favourable UKconsumer background should have led to stronger trading insecond half of Q116
** Next, up 2.6 pct, poised for biggest one-day gain in amonth; stock up 8.5 pct YTD vs c.20 pct rise from M&S (RM: tricia.wright1.thomsonreuters.com@reuters.net)