The exact duration for your flats can be tricky, I have had to use a bit of exposure bracketing to find the sweet spot for each filter when using the H694 and AG12 and then keep these in a library, of course I don't move my rig so this would be harder for you and your container ship worth of travelling gear
. The 16803 seems to be much more forgiving and I shoot for around 30,000 for each filer and this works well.
Mike