At the surgery I worked for we used to say it would take 2 weeks minimum for processing forms. Claims for insurance re holiday cancellation are but a small part of the doctors administrative workload. On average at my surgery (albeit a big one) we had in excess of 300 forms a week to be completed. All patients recrods need to be checked etc. Whilst your form was straight forward, it was probably processed in strictly date order i.e. Not taking priority over adoption forms, mortgage insurance, fitness, DVLA, etc etc. These things take time and cost because they are not part of free NHS services.