Barron's quotes his thinking which is basically that downside risks are hard to quantify...this is a surprise , I expected Baker to significantly raise his PT and certainly not issue a downgrade... would have helped if he gave his upside range on a merger settlement .
The reasoning is most likely that they haven't been able to fill the demand from high net worth clients and they are trying to get selling from weaker hands before this explodes over $15+...same game as always...don't be fooled , because the float is minuscule and they'll have to pay a higher price.
In reading the JPM report it's clear he's ringing the $ register & doesn't want to get caught AGAIN with his pants down in the event the DOJ suit is not lifted. Remember the JPM analyst DOWNGRADED AMRQ when it was $3+ when the DOJ filed suit (only to upgrade again higher when the rumblings of merger success became apparent). JPM has a $29 target on LCC which can get you easily to a discounted value on AAMRQ in the $Mid-Teens$$$---which is about 65-70% higher than today's price.