It wouldn't change anything except reducing the chance of an electric shock to anyone changing a lightbulb. You need to find out if you have 240v between earth and N, which seems likely and then why? The other possibility is your switch drop is not a straight forward switch drop but that seems much less likely.
In fairness, with some experience and decent equipment you could trace that fault fairly quickly. As you mentioned, high likelihood of animal intervention.
It wouldn't change anything except reducing the chance of an electric shock to anyone changing a lightbulb. You need to find out if you have 240v between earth and N, which seems likely and then why? The other possibility is your switch drop is not a straight forward switch drop but that seems much less likely.
In fairness, with some experience and decent equipment you could trace that fault fairly quickly. As you mentioned, high likelihood of animal intervention.