Unexpected behavior CDS API - 6 variables (excluding dimension variables)

Hello,

I'm experiencing a strange (in my opinion) behavior while download data in netCDF format using the CDS API.

Here is how I'm trying to request the data from Python:

import cdsapi

c = cdsapi.Client()

c.retrieve(
'reanalysis-era5-single-levels',
{
'product_type': 'reanalysis',
'variable': [
'100m_u_component_of_wind', '100m_v_component_of_wind', '2m_temperature',
],
'year': '2019',
'month': [
'06', '07', '08',
'09', '10', '11',
'12',
],
'day': [
'01', '02', '03',
'04', '05', '06',
'07', '08', '09',
'10', '11', '12',
'13', '14', '15',
'16', '17', '18',
'19', '20', '21',
'22', '23', '24',
'25', '26', '27',
'28', '29', '30',
'31',
],
'time': [
'00:00', '01:00', '02:00',
'03:00', '04:00', '05:00',
'06:00', '07:00', '08:00',
'09:00', '10:00', '11:00',
'12:00', '13:00', '14:00',
'15:00', '16:00', '17:00',
'18:00', '19:00', '20:00',
'21:00', '22:00', '23:00',
],
'format': 'netcdf',
'grid': '0.25/0.25',
'area': '0/-48/-18/-34'
},
'some_name.nc')

I can download the netcdf without any problems, but as soon as I try to read the file, that's what I get:

6 variables (excluding dimension variables):

short u100_0001[longitude,latitude,time]
scale_factor: 0.000388201867135403
add_offset: -3.75457337339451
_FillValue: -32767
missing_value: -32767
units: m s**-1
long_name: 100 metre U wind component

short v100_0001[longitude,latitude,time]
scale_factor: 0.000463298542471565
add_offset: 1.89131650746705
_FillValue: -32767
missing_value: -32767
units: m s**-1
long_name: 100 metre V wind component

short t2m_0001[longitude,latitude,time]
scale_factor: 0.000533161876697618
add_offset: 297.217384786249
_FillValue: -32767
missing_value: -32767
units: K
long_name: 2 metre temperature

short u100_0005[longitude,latitude,time]
scale_factor: 0.000424499730589574
add_offset: -1.08838516246295
_FillValue: -32767
missing_value: -32767
units: m s**-1
long_name: 100 metre U wind component

short v100_0005[longitude,latitude,time]
scale_factor: 0.000422448398716463
add_offset: 0.298792376874861
_FillValue: -32767
missing_value: -32767
units: m s**-1
long_name: 100 metre V wind component

short t2m_0005[longitude,latitude,time]
scale_factor: 0.000411618716905986
add_offset: 300.820839112517
_FillValue: -32767
missing_value: -32767
units: K
long_name: 2 metre temperature

The way I did my script to treat this data, I always looked for the short name as v100, u100 and t2m, and it worked until today, butnow, I cannot use my script anymore.

So, in summary, my questions are:

1) Why is this happening now? 

2) If this is an expected behavior, what does it mean? What's the difference between v100_0001 and v100_0005?

3) If this is not an expected behavior, is there any work round it?

Thanks in advance!