(1) I've checked the TEMPO issue. This is from the UK ATPL course, which is based on EASA:
"A TREND forecast is valid for 2 hours afer the time of the observation of the METAR, and constitutes the final section of the METAR. The change in weather conditions indicated by the code, TREND, can be further qualifed by the codes, BECMG, meaning becoming, or TEMPO meaning temporarily."
It further clarifies, "BECMG indicates that the change in the present weather will be long-lasting. TEMPO, on the other hand, means that the change is temporary, and that the diﬀerent conditions will prevail for periods of less than one hour, only, and no more than half the time period, in aggregate."
That seems to confirm the reported conditions were indeed BKN012. What you mentioned was a TREND section (which is interesting, I've never seen one).
(2) Regarding what is considered as ceiling. The latest SERA.5005b still specifies that VFR flights within a CTR are, among other conditions, only cleared for a ceiling being at least 1500 ft high. This is valid for UK - see ORS4 No.1195, Belgium - see EB-ENR 1.2-1, and France for instance. So we have to look for BKN or OVC heights, not SCT.
Interestingly, VFR at night in the UK would be authorized for a minimum cloud ceiling at 1500 ft AMSL. I'll assume it's a typo on the CAA website (http://caa.co.uk/Commercial-Industry/Airspace/Rules-of-the-air/SERA-Implementation/).
The cloud base, defined for instance in Belgium as at least 3/8, is used along with visibility to define a COMOPSAIR weather colour state, which "is a guide for pilots and controllers as to the existing weather conditions. ATC will not refuse an approach clearance for the sole reason that the weather report indicates conditions below the published procedure minima." (AIP Be-Lux, AD 1.1-2, 15 Sep 2016).
Moreover, this is used in the military aviation only. So I'm not sure how this is relevant to the original post above?
I'm pretty sure that's also the case for the Wikipedia link you mentioned, whose source are not available anymore but for which one of the main links is labelled "Department of the Air Force. 2010-12-24."