Due to slow processing, the mails from Russia to abroad takes a lot of time to leave the country (Export of international mail).
The recent experience shows these:
Acceptance (Post office 57 in Moscow) > PCI-2 = 7 days
PCI-2 > Customs = 16 days
Customs clearance = same day
Customs > Export = 15 days
Export to Turkey, Istanbul (TRISTE, Arrival) = just 2 days
Delivery within Istanbul = just 3 days