Possible Clues:

• Having fixed opinions
• You'll get no shade of change, or change of shade, out of one that's this (4, 2, 3, 4)
• Inveterate - they do lie down (anag)
• Conservative deeply stained
• Uncompromising
• Invariant in beliefs
• Confirmed they do lie down all over the place
• Unchangeable in opinion
• Hard-core, like an off-colour yarn?
• Such reactionary opinions of noted oldie: why change?