Why else would they release that info?
How could it possibly help in the case other than to push the original narrative that 'Nicola went into the water and no 3rd party is involved' which we have heard countless times from day 1?
I interpreted your original question a bit differently .
I will try to answer this follow-up anyway .
Today's presser and subsequent update , may have helped to quieten rumours/discussion about 3rd party malicious involvement .
It might have made it even less likely , on the count of probability .
But it hasn't squashed it , it may have narrowed it down .
Equally , it has created the foundation for an even more open than before possibilty , that she may have left the area of her own accord ( alone or with the help or non-malicious 3rd party).
It has done nothing , in my view , to increase the likelihood that she may have just fallen in the water. This stays the same , unless you consider truly possible that she was so intoxicated that morning , to have had an episode BECAUSE of her alcohol intake on the day (or the night before).
And i doubt this , because driving a 6 and a 9 yrs old children to school in that condition would be incredibly irresponsible , IMO.
I might have not correctly understood your original question , but sure hope i've given you a bit of context to my original answer.