Other mistake: Mac is leaving a message for Christine. There is a close up of his cell phone. The keypad on the phone has the numbers in the wrong order. On every phone in history the first row of numbers is "123". On Mac's phone it is "789", like a computer keyboard.
Factual error: Towards the end, Eva Mason blows up Leonard Brooks' flat in an attempt to kill him, by heating up gas from the stove using an uncovered light bulb. This wouldn't work as shown as the filament from the bulb would burn out before igniting the gas - and besides, a spark from the light switch would have ignited it first.
Continuity mistake: The dead body of a girl is in the autopsy room. There is a closeup of her face on a TV monitor. Her hair is wet and tucked under her head and the v-shaped stitches on her torso are reddish in color. Next shot her hair is spread out and the stitches on her torso are blueish.