Delete all rows between two values in a dataframe that repeat multiple times in a column
You can achieve this by forward filling the blank values, and then selecting only those with new_records:

df.fillna(method='ffill')

df = df[df['column_A'] == 'new_records']


Depending on the actual values in your data frame, you may need to first replace what appear to be empty/space strings with NaN's:

df['column_A'] = df['column_A'].replace(r'^\s*$', np.nan, regex=True)