What makes telly so awful about the first of December, according to the Julian calendar (3,5)
I believe the answer is:
old style
'julian calendar' is the definition.
(synonyms)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for old style that I've seen before include "Traditional, retro" , "Traditional type" , "how Julius arranged his dates" .)