When Calendar Dates Change
When the calendar the calendar dates change, you must run either the Align Time-phased Dates process or the Respread process.
When there is a change in the project dates (defined on the General tab of the Project view), you must run the Align Time-phased Dates process. The Align Time-phased Dates Wizard will adjust the time-phased resource records on the project and align them with the new calendar dates.
When there is a change in the fiscal calendar of the project (for example, changing the calendar from a monthly to a weekly calendar), you must run the Respread process.
Since Respread is going to change the budget, you should backup your project before running this process. In addition, you should run a time-phased report of your budget before running the Respread process.
For example, if the period changes from Dec 31, 2010, to Dec 24, 2010, some of the time-phased budget data stored in the December period needs to be moved to the next period, which is January. The value to be moved is based on the spreading option selected and corresponds to the value that was budgeted in the in the last week of the year. Since this changes the fiscal year budget of your project, you should always take care when running Respread.