Disco 1 Modern Bio-Diesel corrode rubber ?

Back in the day when I owned a VW there was a spate of engines catching fire due to the increased ethanol content in petrol corroding rubber fuel lines.
I put some posh stuff in the 300 the other day, and i have noticed all the top hoses have started ****ing diesel everywhere (thought these were modern ones). Upon replacing them I noticed the old ones are all cracked
Could this indeed be the ethanol, or just a symptom of the mental heat we have been having (or should these generally be changed every year or so anyway?)

Ethanol can certainly perish certain rubbers/ plastic/cork but yours was probably down to age and the ethanol was the last straw, ethanol is going up to 10% soon for petrol cars and guaranteed to cause mayhem on many older
Vehicles,

I am led to believe BP premium/posh petrol actually has no ethanol, even if the pump says E5 it still has none in it, apparently.

Currently Esso super in the southeast doesn’t have ethanol, ( as far as I know it’s the only company not using ethanol in there premium fuel). different refineries around the country in the main do supply with 5% and going upto to 10%, it’s not just the corrosive nature of ethanol that’s the problem it also absorbs
Water if left standing in a fuel tank, eventually the Ethanol will evaporate leaving behind water to corrode the tank and fuel system components,
One of the biggest problem is with composite fuel tanks , a lot of small aircraft and boats have these and the ethanol will turn the fibre class to jelly and has effectively written of some small aircraft where the fuel tank is bonded in the wing,
Bad new for a lot of people and they will certainly not drop the cost of fuel when it’s added , a case of bending over
And being shafted by the petroleum companies again,

There have been warnings on the tele to check if your vehicle is ok with the new fuel, no advice on what to do if it isn't though

Slightly confused: what does ethanol in petrol have to do with your 300 diesel?

Bio diesel has ethanol in it as well