The claimant was employed by the respondent from 15 June 2009 under a contract that allowed for variable hours. The remuneration payable for any week varied according to the number of days or hours of work performed. The claimant was entitled to 5.6 weeks of leave per year and the leave year began on 15 June. In November 2012 the claimant requested a week of paid leave but the respondent informed her that she had exhausted her entitlement, which was calculated at the date on which leave was taken, based on the working pattern for the 12-week period prior to the leave. Since the claimant had taken her leave at a time when her work pattern was one day per week, she had taken the equivalent of 7 weeks of paid leave, and accordingly exhausted her entitlement to paid annual leave. In subsequent Tribunal proceedings, the claimant was initally successful but on reconsideration the Brimingham Employment Tribunal sought a preliminary ruling on whether, as the respondent contended, that EU law does not provide for a new calculation and that, therefore, Member States are not required to make such an adjustment under national law.

In this judgment the CJEU identified 5 questions

1. is the "pro rata temporis principle", as set out in clause 4.2 of the Framework Agreement, to be interpreted as requiring a provision of national law, such as regulations 13, 13A and 14 of the Working Time Regulations, to have the effect that, in circumstances where there is an increase in the working hours of an employee, the amount of leave already accumulated must be adjusted proportionally to the new working hours, with the result that the worker who increases his/her working hours has his/her entitlement to accrued leave recalculated in accordance with the increased hours?
2. Is either clause 4.2 of the Framework Agreement or Article 7 of the Working Time Directive to be interpreted as precluding a provision of national law, such as regulations 13, 13A and 14 of the Working Time Regulations, from having the effect that in circumstances where there is an increase in the working hours of an employee, the amount of leave already accumulated is to be adjusted proportionally to the new working hours, with the result that the worker who increases his/her working hours has his/her entitlement to accrued leave recalculated in accordance with the revised hours?
3. If the answer to question 1 and/or 2 is yes, does the recalculation apply only to that portion of the holiday year during which the employee worked the increased hours or to some other period?
4. When calculating the period of leave taken by a worker, is either clause 4.2 of the Framework Agreement or Article 7 of the Working Time Directive to be interpreted as requiring a provision of national law, such as regulations 13, 13A and 14 of the Working Time Regulations, to have the effect of adopting a different approach as between calculating an employee's allowance in lieu of paid annual leave entitlement upon termination and when calculating an employee's remaining annual leave entitlement when they remain employed?
5. If the answer to question 4 is yes, what is the difference in approach required to be adopted?'

They concluded on questions 1-3 that

"that clause 4.2 of the Framework Agreement on part-time work and Article 7 of Directive 2003/88 must be interpreted as meaning that, in the event of an increase in the number of hours of work performed by a worker, the Member States are not obliged to provide that the entitlement to paid annual leave already accrued, and possibly taken, must be recalculated retroactively according to that worker's new work pattern. A new calculation must, however, be performed for the period during which working time increased."

and on questions 4 & 5 that

"clause 4.2 of the Framework Agreement on part-time work and Article 7 of Directive 2003/88 must be interpreted as meaning that the calculation of the entitlement to paid annual leave is to be performed according to the same principles, whether what is being determined is the allowance in lieu of paid annual leave not taken where the employment relationship is terminated, or the outstanding annual leave entitlement where the employment relationship continues."

Read the full case report on the Europa website here.