It's been 2 1/2 months since I picked up my new Volt. During that time I've seen a slight uptick in the battery range. It started off somewhere in the 58 mile range but yesterday started out at 63. Anyone else observe this? Is there a break in time for the battery where it starts to hold a charge longer? Not complaining and love to see it go higher before the weather turns cold (currently sitting at 240 total MPG...woo hoo!)