Christmas favourites Quality Street have undergone an unwanted makeover after makers Nestlé were forced to change the wrapping of two of the chocolates.
A shortage of foil means that the green triangle and orange crunch have been temporarily wrapped in different colours.
Some festive boxes will now include the triangle covered in an unfamiliar gold colour, while the octagonal crunch chocolate will be wrapped in a dark bronze foil.
The "rare" packs were produced at a Halifax factory, after stocks of green and orange foil could not cover a planned production run last week, said Nestlé.
Quality Street's senior brand manager Jemma Handley told The Grocer: "I promise this isn't a publicity stunt.
"We've not added full size chocolate bars to the tin or removed the coconut flavour from a handful of tubs.
Watch: Meet the cheery residents of Britain's 'real-life' Quality Street
"We simply didn't have enough of the right coloured foil to cover the production run of the two sweets in question and, rather than leave them out of the selection altogether, we decided to use different colours for a very limited period.
"We are fairly sure this is the first time this has happened so anybody who finds a green triangle or an orange crunch in a different coloured foil will have something of rarity on their hands. It's the same hazelnut and orange sweets inside the wrappers, regardless of their colour."
In August, Nestlé shrank the size of its Quality Street tubs for the first time in three years in a bid to mitigate soaring costs.
The 650g tubs that were on sale last Christmas have been replaced by 600g ones.
The popular boxes were downsized from 780g to 750g in 2017, and again to 720g in 2018. Nestlé shrunk them again in 2019 to the 650g tub size.
Earlier this month, Mars Wrigley announced that Bounty bars would be be removed from Celebrations chocolate tubs in a pre-Christmas trial, after claiming that 39% of consumers wanted the coconut-flavoured treats banished for good.
However, the move proved to be a publicity stunt and the option of swapping Bounty boxes for Maltesers was a short-run trial at just 40 select supermarkets.
Yahoo News UK has contacted Nestle for comment.