When changing the fixed asset depreciation method from straight line to an accelerated method in the asset book screen, clicking save reset the depreciation method back to straight line.
In order to understand the reason, it is important to understand the function of the switch-over method. The switch over method provides a choice of no switch or straight-line. At the beginning of each year, Dynamics GP analyzes the switch-over method against the depreciation method chosen. Depreciation will be calculated based on whichever method provides the most depreciation.
For this reason, straight-line is not a valid switch-over method when choosing an accelerated depreciation method. If changing from straight line to any double declining balance, you need to choose no switch-over in order for the record to save.