An interesting problem
@AsterixTG. I often see lights high in the hills, various numbers and random movement makes me think it is just people walking. Personally I try to rely on night vision, and I haven't been out in real darkness for a long time.
So, if I was in trouble I'd try to make a more obvious signal, pointing torch towards a farm, village, road junction, trying a few different directions.
But then what? Do people still recognise six flashes as a distress signal? I mean average "youth of today", not regular walkers? Does the smart phone generation even look up towards the hill tops? Would a strobe, white or red, be better at attracting attention? Would a continuous stationary light be noticed as something abnormal?
I'd be interested to know what you think.