It's not true, we won't be returning to the imperial system, for one hardly anyone under 60 remembers how it worked... and we've have a decimal system with money since 1971 long before we joined the EU...
We have never even after joining the EU..changed our road signs to KM's.. we have always continued to use MPH... we still ask for a Pint in our pubs.. that's never changed, no-one has ever asked for 1/2 litre or a litre of beer...
In fact many people older than me ( mid 60's )...still ask for a pound or a quarter of something in the butchers or at the Deli... although officially since joining the EU at the shops it's Kilo and grams.. and ready prepared food is sold in Metric
Contractors all work in metric , have done since 1975 and construction built since that time are measured in Metric...so it would cause Chaos to revert back...
I still think in Pounds shillings and pence sometimes.. ( I'll often think wow that apple just cost me the equivalent of 17 shillings )... and I always measure in feet and inches, and then have to convert it to Metres and centimetres.. it's instilled in me.. it's what I learned as a child.. and I was in my 3rd job working in a Jewellery shop before we changed to the Decimal system , and we had to change all the prices of everything, not even knowing exactly what the conversion was...
Anyway , we will not be reverting as a nation back to Imperial , what stores will be permitted to do however is sell in Imperial measures to customers if that's their preference... ( whereas while we were in the EU, sellers had to always market their goods in metric ) ...overall the metric system is much easier to learn... my generation and those before me were obviosuly just mathematical geniuses to be able to deal with Imperial measurements, especially in mental arithmetic