Might need to use AST Break Clause over flatmate's objections - possible?


I’m on a year-long AST in a flat share with 1 other person. I’m currently unemployed and have been looking at jobs outside my current city. As such I might find myself position of needing to move out, yet being stuck in an AST which doesn’t end until July.

The AST does have a break clause: For reference, the specific wording of our break clause is “The Landlord and Tenant agree that they have the right to terminate the Tenancy after the first 7 month period…[with] the Tenant giving 1 month’s notice in writing in line with the rental payment date. When the notice period expires the Agreement shall cease.” The ‘Tenant’ in the AST is defined as both of us forming forming ‘one person’.

My question is - what options do I have to enact the break clause unilaterally? My flatmate’s a decent guy, and we will likely be able to come to some sort of agreement. However, what if he decides to play hard ball and refuses to leave until the AST ends? The above would suggest that the break clause has to be signed by both of us to be valid and that I cannot do this.

For reference I plan to move out in July anyway, so this situation would merely bring forward the inevitable. My worry of course is that I get a great opportunity elsewhere, but my flatmate refuses to agree to use the break clause, thus meaning I have to choose between turning the job down, or taking it and paying the rent on this place until July. Hopefully I’m worrying over nothing, but I want to know how I’d stand in a worst case scenario.

Any advice appreciated,
A. Renter