Non compete clause in employee handbook.

Hi all, based in Northern Ireland. I’ve been offered a job recently with an almost 2x salary but it is with a direct competitor. I’ve worked in the role less than a year (but past my probation period).

I read the contract I signed with my current employer and it says “This Statement, together with the Employee Handbook, forms part of your Terms and Conditions of Employment and sets out particulars of the main terms on…”

At the bottom where I sign it says “I hereby verify that through signing this Statement of Main Terms of Employment I have read, understood and accepted all terms and conditions in relation to my employment…”

I am worried the employee handbook contains some form of non compete clause which would affect my ability to work for the competitor. I have never been presented with the employee handbook & was never presented it when I initially signed the contract.

If it turns out the handbook includes a non compete clause, would it be enforceable based on these circumstances?

Thanks in advance!