Migrating WebSphere ILOG Rules for .NET from V3.0 to V7.0 or V7.1 can reset dates in decision table rules back by seven or eight hours. This only occurs in decision tables, and can occur with a date, universal date or a simple date. With simple dates, the time is systematically set back one day.
The error is the result of a time-zone discrepancy between the dates in the rules and the dates in the user data. The migration considers all dates in decision tables to be in GMT, and converts them into the time zone used where the migration is made.
Resolving the problem
Change the machine time to GMT before the migration, and then change it back afterward.