Tuesday 22nd December: SR-819
Wednesday 23rd December: Tithonus
Thursday 24th December: One Son
Friday 25th December: Agua Mala
Monday 28th December: Monday
...so, they've missed episodes before, but...I'd've thought if you're going to show the second part of a two-parter (One Son) it would kind of make sense to show the first part (Two Fathers) as well..?