My wife and my son have UK visas in previous passports, and traveled to the UK in August with both passports.
My wife has the landing stamp in her new passport, with a note saying VIPP, as expected.
My son has the landing stamp in his expired passport even though both passports were together and the new one was scanned. This looks like a simple mistake to me, the officer got a little distracted when another officer came to his desk asking for something else.
We have since left the UK after completing our tour. I'm not too bothered about it, but for the sake of knowledge; Should I request correction somehow?