Different email validation results for different socks5 proxies

[hack3r-0m]

When using 188.166.83.17:1080 output is :

{'address': Address(name='', addr='X', username='Y',
domain='Z'), 'valid_format': True, 'deliverable': True, 'full_inbox': False,
'host_exists': True, 'catch_all': True}

When using 78.46.218.20:13414 output is :

{'address': Address(name='', addr='X', username='Y',
domain='Z'), 'valid_format': True, 'deliverable': False, 'full_inbox': False,
'host_exists': True, 'catch_all': False}

The used email for the above test is INVALID.

Why different proxies are giving different outputs for the same email?

From deliverable, full_inbox, and catch_all, which factor or combination of factors I should rely on and why?

[Natteo]

Same problem... under proxy the script is unreliable

[pavanmkumar]

Same problem here, did you find any solution.