Not sure it's sneaky but it could have been advertised I agree.
.. and yes it's all because of Brexit and the Schengen area so I understand.
'The move appears to be a belated effort to conform with the Schengen Border Code. These are the rules which are likely to regulate access for British travellers to most EU nations after Brexit.
The code does not recognise passports which are valid for more than 10 years.'