White filled cells in Flow Hive super 7 frame Langstroth

We did not see this type of honey at all in the July 40 lbs of honey collected then.
There are about I would say 10 cells that appear white and I am wondering if the bees have collected nectar that has set?
I notice that one cell in particular has the same runny honey at the cells base but the light colour almost white is on top to the brim of the cell. There are no capped cells. We thought that we might get a second harvest but the nights are getting cooler at one night 4 degC.
The 7 Flow Hive units are about 80% full. Of course the cells at the rear are the ones that can be seen. The outer side panel is seen to be not capped at all.
We are in Nottingham UK and 350 metres from the Wollaton Hall Deer Park. We would appreciate your thoughts on what the white cells contain?