I am a UK citizen living abroad with my wife and child who hold foreign passports. My child also holds a UK passport as the dual nationality rules for children in his country of birth are a bit vague - current practice suggests that he is allowed to hold both foreign and UK up to the age of 21, after which he has to select a single nationality as his country of birth does not recognise dual nationality after that age.
When we entered the UK recently (with wife and child using foreign passports) the border official said that due to a rule change earlier this year she could no longer stamp my child's foreign passport because he also held a UK passport. She didn't even ask to see the physical UK passport as it appeared it was visible on her computer. This had not happened on previous visits.
While this is not an issue for staying in the UK, there is a concern that when he goes back to his country of birth the foreign border official may query how he entered the UK without a stamp on their foreign passport, potentially losing his original nationality and separating child from mother because of the dual nationality uncertainty.
Does anyone know of a specific link online to the 'rule change' the border official is referring to?
I am familiar with the suggestion at case 3 of the following link I have two passports/nationalities. How do I use them when I travel? Any other suggestions for future travels?