Land Rover Repair: 2004 disco question

Question
I have a 2004 discovery.  A few weeks ago I started having problems with her starting after being in the parking lot at work all day.  I went and got a new battery.  Now i'm still having problems.  after sitting in the parking lot at work all day she will turn over but not start, so I turn off the ignition and turn it back on and then she will start.  only does this after work.  when she sits at home in the evening i do not have this problem in the morning.  The mechanics are at a loss and want to replace my fuel filter, even though they are not sure that is the problem.  any suggestions/help would be greatly appreciated.  PS I live in texas and it's been very hot, not sure if the heat has anything to do with it.

Answer
My first suggestion would be to find a qualified Land Rover service person or shop, and have them diagnose and fix the problem.  If you want to guess, my money would be on a crank or cam sensor not a full filter.  The rule filter has about zero chance of resolving this.  But like I said, in the absence of actual proper diagnosis we are just speculating