Your situation involves potential claims under UK employment law that do not require the standard two-year service threshold. Both victimization under the Equality Act 2010 and unfair dismissal are available to you if the dismissal was genuinely triggered by your sexual harassment complaint, even if the employer cited sickness absence as the formal reason.

Victimization occurs when an employer treats an employee poorly because they made a protected act—such as reporting sexual harassment. If your dismissal followed your complaint, it is illegal regardless of service length. The employer's stated reason (intermittent sickness) may be a pretext. Additionally, if your sickness was caused by the harassment itself (stress, anxiety, or depression), and the employer failed to make reasonable adjustments or investigate properly, further discrimination claims may arise.

For a capability dismissal based on sickness to be fair, the employer must act reasonably: investigate, consult with you, consider medical evidence, and explore alternatives such as adjustments or redeployment. If these steps were skipped, the dismissal is likely unfair.

Immediate action is critical. Gather all evidence now: your formal complaint, medical records linking illness to the workplace, correspondence about dismissal, fit notes, performance reviews, and witness details. You must contact ACAS (Advisory, Conciliation and Arbitration Service) to begin Early Conciliation—this is mandatory before filing an Employment Tribunal claim. There is a strict three-month-minus-one-day deadline from the dismissal date. Seek advice from a solicitor or Citizens Advice Bureau to protect your rights and assess which claims best fit your evidence.