The nun says there have been only twenty-three miracles at Lourdes (up to the time In which the film is set). There actually had been sixty-two. UPDATE: At some time prior to April 2024, the filmmakers must have changed the film to correct this, because the line now states sixty-two.
They reference Laura Linney's character having been gone 40 years. Even if she had left at 16 that would still make her almost 60, much older than Laura Linney. And despite allegedly being the same age growing up, Kathy Bates is closer to Maggie Smith in age.
At one point in the film, Maggie Smith's character is in a wheelchair which is very clearly a modern make and style vs. the 1960s era the film is set in.
The characters are said to live in Ballygar. Yet, Lily walks to a seaside shrine to the son drowned in the sea. Ballygar is more than 30 miles from the sea.
There's no explanation for where Chrissie and Lily's tickets come from. There are only two tickets from the talent show which cover Dolly and her son. Chrissie gives her ticket to the priest who passed it on to Eileen. So there is no explanation for where the extra "tickets" come from or how they are able to go without vouchers for the trip to Lourdes.