The renewal date of you hosting depends on the plan you have purchased. At Papaki.gr there are 1-year, 2-year, 3-year, 4-year and 5-year plans, which means that you can renew whenever you wish, before the expiration date of each plan. 

You will notice that the longer a plan lasts the cheaper the price is, therefore you earn money and time by avoiding multiple renewals, when choosing a longer plan such as the 2, 3 or more year plan.

Don't forget that you get a 90 Days Money-Back Quarantee from the date you purchase your plan.