Stranger at the Gates (Part 1 of 2) - S2-E3
Other mistake: In a previous episode ("A Breath of French Air") Ma explains to a french fisherman that she's used to cooking fish as the Larkins have both a pond and a river near their home. In this episode Montgomery complains that there is nowhere around for him to fish.
When the Green Woods Laugh (2) - S1-E4
Other mistake: The court summons is delivered and states the case is to be heard on July 7th, which is the same date as Mariette's wedding. When the case starts, the charge is read to the court and states the date of the alleged assault of August 23rd, which would be 6 weeks in the future.
