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Greek gmt is +3? Friday at that time its impossible for me, I can only be available till 8 AM -11 AM friday. The Saturday i can play at th same time (8 am - 11 am) and any time after 21 PM.
He prefers either 14:00 - 20:00 Greek time Friday or 14:00 - 18:00 Greek time Saturday. If you are 100% unavailable at those time periods, he can also play 14:00 - 20:00 and 23:00 - 02:00 Greek time tomorrow.