2022-02 data with multiple expver states in netCDF data download

We have been using the API to download data (reanalysis-era5-single-levels) for about one year. We have been updating out dataset of monthly data by expanding coverage for the years 1979 through 2022. We request data to be downloaded as netCDF format. All was fine, until fetching the monthly data for 2022-02. This resulting dataset was twice the size of all the monthly downloads ( ~14GB vs~7GB).  A deeper examination indicates, the 2022-02 dataset has two expver values within it. No other month has this. How can we find out what these two expver values refer to?

Thank you,


please have a look at the following link: https://forum.ecmwf.int/t/era5-cds-requests-which-return-a-mixture-of-era5-and-era5t-data/781