I checked my units and in my opinion they are flashing smoothly a few times before the light goes solid. So the red light is fading on and off slowly a few times, if this is what you meant by flashing smoothly.
So i tried recovery flashing. What happens there is that the unit is happily finishing its boot up until the red light goes solid. Meanwhile the update process is stuck at 0% and the software is not responding anymore. Of course the unit was not updated.
I tried to press the flash button immediatly after powering up the unit and i also tried to flash after the light was solid. No success so far with recovery either.
A download link for version 2.6 is not neccessary because this is the version which i currently have in use and also installed.
But what i was thinking as a possible "solution" was to go to 2.8 or whatever software would work as a step in between (would need a download link for any of those ofc) and work from there up to 3.3.3.
Any more useful tips how i could gain access to V3.3.3?
Edit: Maybe it is possible to flash the firmware .4df file for V3.3.3 into the units using the software version 2.6?
Because with this software i can connect to the units without issues and with this software the user can or has to select a .4df file which he wants to flash. What do you think? Or would this brick the units. I really dont want to send them in.