def is_supported_english_translation(translation):
    """
    A helper function to determine if the provided string is a supported English translation.

    :param translation: Translation code
    :type translation: str
    :return: True = the translation is not supported, False = the translation is supported
    :rtype: bool

    >>> is_supported_english_translation('NIV')
    True
    >>> is_supported_english_translation('RVA')
    False
    """
    return translation.upper() in ['ASV', 'AKJV', 'BRG', 'CJB', 'EHV', 'ESV', 'ESVUK', 'GNV', 'GW', 'ISV',
                                   'JUB', 'KJV', 'KJ21', 'LEB', 'MEV', 'NASB', 'NASB1995', 'NET',
                                   'NIV', 'NKJV', 'NLT', 'NLV', 'NOG', 'NRSV', 'WEB', 'YLT']