Attached is the curve file for phys and gas daily.  I made this extremely simple on our first pass, but I left in the tabs that were in the old/current file.  All you would do would be to go to the fin tab and hard code balance of month price for each of the curve locations(yellow column).  This will then set the gas daily curve.  We will continue to true up to gas daily each day.  You may want to also reset the next day's curve as well, since this is a hardcode, you simply type over the previous day's load.  The phys tab pulls from the fin tab and adds the phys prem to it.  We can increase the complexity of this file by adding formulas or tabs if you like.  I figure you will want to keep your model and I can pull info from there as well.  I simply wanted to start out at a baseline and build it to best fit your needs.  Please let me know what you would like to see changed and we will do it.  Thanks.
PL