Temporary speed restrictions on motorways in amber with amber flashing lights advisory or compulsory ?
Advisory - but if it goes ■■■■ up, it will be questioned as to why you didn’t follow the advice.
Advisory always have been.
Only rhe red circle with white background is compulsory.
Wouldn’t it be easier to show them the Hw code
that was exactly what i said today vindicated cheers
Advisory. 
Highway code Rule 261
You MUST NOT exceed 70 mph (112 km/h), or the maximum speed limit permitted for your vehicle (see Speed limits table). If a lower speed limit is in force, either permanently or temporarily, at road works for example, you MUST NOT exceed the lower limit. On some motorways, mandatory motorway signals (which display the speed within a red ring) are used to vary the maximum speed limit to improve traffic flow. You MUST NOT exceed this speed limit.
Mandatory, end of argument. 
Popcorn ready… 
Gangan:
Highway code Rule 261You MUST NOT exceed 70 mph (112 km/h), or the maximum speed limit permitted for your vehicle (see Speed limits table). If a lower speed limit is in force, either permanently or temporarily, at road works for example, you MUST NOT exceed the lower limit. On some motorways, mandatory motorway signals (which display the speed within a red ring) are used to vary the maximum speed limit to improve traffic flow. You MUST NOT exceed this speed limit.
Mandatory, end of argument.
He didn’t mention them speed signs, he said the ones in Amber. They don’t have a red ring so I think you’ve just further proved his point to be fair 
Tempory roadwork limits are red circles on white background so compolsory. Amber numbers are advisory.
Gangan:
On some motorways, mandatory motorway signals (which display the speed within a red ring) are used to vary the maximum speed limit to improve traffic flow. You MUST NOT exceed this speed limit.Mandatory, end of argument.
Not those signs, these ones.
Which says in the Highway Code: Temporary maximum speed advised
Some people can’t read
Glen A9:
Gangan:
On some motorways, mandatory motorway signals (which display the speed within a red ring) are used to vary the maximum speed limit to improve traffic flow. You MUST NOT exceed this speed limit.Mandatory, end of argument.
Not those signs, these ones.
Which says in the Highway Code: Temporary maximum speed advised
Advisory, end of argument
You may also see signs at the side of the road stating a “maximum speed”, particularly on corners on motorways (e.g. the M25 anticlockwise onto the M4 Westbound has a sign saying “Maximum speed 40 mph”. These are also advisory.
In all cases, if the sign, or the official documentation (e.g. Highway Code) uses the phrase “Speed Limit” then it is compulsory, but if it says “Maximum Speed”, then it’s advisory.
Speed limits are either black text on a white background inside a red circle, or white lights inside a circle of red lights on a black background. Anything else is not a speed limit, and is advisory.
As others have said, whilst exceeding a posted maximum speed is not illegal, it will count against you should you be involved in any incident.
As a point of interest, the government recently had to rewrite the legislation in this area because it was proven that some of the variable speed limit signs on motorways were unenforceable because the numbers were in the wrong typeface (i.e. the numbers weren’t the exact shape as specified in the regulations).
What was that book they used to make us read?
I’ve always gone with the school of thought that if its not surrounded by a red ring then its always “advisory”. I do wonder if folks read the highway code when charging through the varible speed limit zones on the motorway. Those cameras on the M25 near Rickmansworth are forever going off.
stick to what the speed limit says,no problems then
or…just do what most do and ignore both, just be a bit more aware on the mandatory stretches and see how you get on…works for me. 
Eric Rambler:
What was that book they used to make us read?
The Beano lol
My mate says speed limits only count when there are cameras about 
dri-diddly-iver:
My mate says speed limits only count when there are cameras about
Thats obvious, why make a car which does more than 70mph if the most you can legally do is 70mph??
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