According to this article reduced VAT rates of 10% and 15% were consolidated into a single reduced VAT rate of 12% starting from 2024-01-01. Currently the JSON file still contains the older VAT rates.
Nicely spotted @mtarnovan - I was able to confirm your findings and added the new consolidated reduced rate in d5eaabaf37e3259f0e8533e3eb7a69e407aab68b. Thank you for contributing!
According to this article reduced VAT rates of 10% and 15% were consolidated into a single reduced VAT rate of 12% starting from 2024-01-01. Currently the JSON file still contains the older VAT rates.