CandleLight001 and Enzo Morocioli,
What you are describing is what happens after your flashlight: 1) discovers that there is a problem with the available power, 2) has reduced the power to compensate and 3) is now trying to see if there is enough power to use the requested power level. The code is there to allow automatic recovery just in case a power glitch is detected - which is difficult to distinguish from a dying battery. This behavior has been in our flashlight designs for many years and is documented in the EDC Ultimate/Basic User manuals.
You will notice that once your flashlight has stepped down with a dying battery, you can turn your flashlight off and back to the previous setting and it will "ramp up" until it reaches the selected brightness or until the battery cannot provide the power and steps down again. Most batteries that are just beginning to die will recover enough after the light is turned off for 10 to 20 seconds to be able to power the original brightness level for at least a few seconds.
The primary reason for this behavior was to handle intermittent conditions that can develop with normal use. Once a power glitch is detected - which looks just like a dying battery - the flashlight blinks and the output power is reduced. The only way to get back to the previous output power level is to turn your flashlight off. When your flashlight is turned back on, the software assumes any previous restriction in output was a power glitch. When an output power level is selected that is higher than the restriction, your flashlight "ramps up" to test the power capability of the battery. If the problem was a power glitch or if the battery has recovered temporarily, ramping continues until you get the selected power level.
The thing you will notice about this algorithm is that the power issue actually happened the previous time the setting was used. The recovery does not happen until the next time the setting is used and then only after you turn your flashlight off and back on again. So the recovery may not be attempted until minutes, hours or even days after the power issue was originally detected.
The Ra Twisty uses a twisting motion to switch power settings and uses conductive threads for transferring power. During that twisting motion, the threads are active, which can lead to a power glitch. This is especially true if you apply about 4 pounds of compressive pressure between the head and tail, which will in turn relieve pressure on the threads. This can lead to an intermittent connection while changing power levels. This condition is much more likely to happen at higher power settings. Giving a slight tug on the two parts while twisting them will prevent this from happening.
Henry.