Have Kent County Council withdrawn their advice to schools about planning for disruption then, given that it’s now unnecessary?
I don't know - but I've just found this on the local news website (from January - before the extra contingency planning);
Education chiefs downplay Brexit impact on schools
"Ian Watts, area education officer at Kent County Council, said: “We acknowledge that if any schools are affected, the number is likely to be low."
"However, as with all aspects of emergency planning, it is prudent to have awareness of the possibility of heavier traffic and the effect that it may have on the need to manage pupil and staff movement around the external school site in such circumstances."
"Mr Watts said:“At this stage we cannot easily predict the eventual impact of the UK exiting the European Union, but it would be remiss to assume no impact."
Air pollution appears to be an ongoing problem for Kent.
www.kentonline.co.uk/kent/news/kcc-seeks-to-quell-concerns-over-brexit-impact-on-schools-197522/
Latest online advice for Kent residents - it doesn't sound like they are expecting severe disruption to me:
Brexit travel and transport
"Some communities may experience disruption to local road networks in the event of a no-deal EU exit."
www.kent.gov.uk/about-the-council/britain-leaving-the-european-union/travel-and-transport