Lease Break Clause Interpretation and Tenant Dispute

I'm a landlord with a commercial lease that includes a break clause. My tenant claims they can exit early citing ambiguous wording in the clause about notice periods and conditions. I need clarity on whether their interpretation is legally sound under the lease terms. The property is in England and this situation needs resolving quickly as the tenant is threatening to abandon the property. I'd also appreciate advice on my options if they proceed with an early departure.