I received the following reply from Eurotunnel Customer Service yesterday...
Thank you for contacting us.
The European Union have introduced a new Entry/Exit System (EES) and this will apply to non-EU nationals (including UK citizens) when entering or leaving the Schengen area. This is not a LeShuttle initiative, but we’ve been working closely with the relevant authorities to ensure your journey through our terminals remains smooth and efficient. While the new system started on 12th October, customers travelling with their cars will not see any changes when travelling with us until early 2026.