When Jelena returns home from a "holiday of a lifetime" travelling around South America later this year, she faces being told she can no longer enter the UK.
The British-Latvian dual national is among those who say they have been caught out by upcoming changes to passport rules for dual nationals, which are due to kick in on 25 February.
Entry requirements for dual nationals are being overhauled as part of sweeping changes to the immigration system the government says will streamline and modernise the UK border.
But for Jelena, who has lived in the UK for 16 years, the changes are a "betrayal", and others in the same situation have told BBC News the prospect of being denied entry is causing anger and concern.
Here are how the new rules will work - and why Jelena and others like her are furious about it.
