Is Zakat obligatory on the sum of 800,0 Syrian Pounds currently available, or after the passing of a full year, knowing that a portion of this sum (600,0 Pounds) is the proceeds of a جمعية (rotating savings and credit association)?

You must calculate the time when the owner of the nisab (minimum amount subject to zakat) reaches puberty. If a full Hijri year passes, you should pay zakat on it, provided it has not fallen below the nisab. Any increase resulting from trade is subject to zakat along with the principal. As for money acquired during the year that is not an offshoot of the principal, according to the majority of scholars, you should assign it an independent hawl (zakat year), or you can pay zakat on all of it along with the principal, as hastening zakat is permissible. Abu Hanifa is of the view that acquired money is subject to zakat along with the principal, whether it is an offshoot of it or not. As for the installments of a cooperative society that have not been collected, their ruling is that of a debt. If the debt is owed by a solvent and willing person, you are obligated to pay zakat on it when a full year passes, whether you have collected it or not. Some scholars permit the option of either paying zakat on it along with your wealth at the end of the year or paying it upon collection for the past years.