Will the ceasefire plan last and, if so, for how long?

Breaking down the US-Russia ceasefire plan for Syria
RT News | Feb 22, 2016
http://on.rt.com/756d

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Following Moscow and Washington’s announcement of a joint ceasefire deal for Syria, the war-torn country may be on the verge of the biggest peacemaking breakthrough since fighting broke out there five years ago. Here is how the proposed truce should work:

When does it start?

The ceasefire will become official at midnight Damascus time on Saturday, February 27 (or on Friday at 22:00 GMT). Those who subscribe to the agreement have to publicly declare that they will desist from hostilities by a deadline 12 hours before the ceasefire comes into effect, and inform the White House or the Kremlin.

Who does it apply to?

It is clearer which parties it doesn’t apply to: “‘Daesh’ [Islamic State], ‘Jabhat al-Nusra’ [an al-Qaeda offshoot], or other terrorist organizations designated by the UN Security Council,” according to the Joint Statement. The Syrian government, as well as the oft-mentioned “moderate opposition” factions and the Kurds, will have to take it upon themselves to put down arms – or face consequences.