"Eastern Ghouta: What is happening and why" Topic

"Siege: Eastern Ghouta has been under siege by the Syrian government since 2013, and is the last rebel stronghold near the capital.

De-escalation zone: Turkey, Russia and Iran agreed in 2017 to designate Eastern Ghouta a "de-escalation zone", in which Syrian and Russian fighter jets were expected not to fly.

Relentless bombing: On Sunday, February 19, Syrian government forces backed by Russian warplanes escalated the offensive on Eastern Ghouta, with relentless bombing that killed hundreds of people within days. Amnesty International said this amounted to war crimes…."
Main page
link

Amicalement
Armand

When this first kicked off, the SAA had assembled the following units for the offensive:

Tiger Forces Division;
14th Special Forces Division;
1st Armoured Division;
4th Mechanized Division;
9th Armoured Division;
Republican Guard 104th Brigade;
Republican Guard 105th Brigade;
Republican Guard 106th Brigade.

The equivalent of an entire Soviet artillery division was deployed to East Damascus.

The start line:

And today:

Map update: Syrian Army liquidates 85 percent of East Ghouta pocket and banishes three rebel force groupings in month-long offensive
By Andrew Illingworth – 01/04/2018

BEIRUT, LEBANON (1:07 P.M.) – With the Syrian Army now in control of the districts of Jobar, Zamalka, Arbeen and Hazzah in Damascus' East Ghouta region, some 85 percent of what was rebel-controlled territory east of the Syrian capital just over one month ago has since fallen to government forces.
The Syrian Army ‘Damascus Steel' offensive has seen the capitulation of three major rebel force groupings – represented by Faylaq al-Rahman, Ha'yat Tahrir al-Sham and Ahrar al-Sham – that once seemed unbreakable in their resolve to never leave their positions east of Damascus.
Now the East Ghouta pocket consists of just one stronghold, the city of Douma. After a week of negotiations it appears that some agreement has finally been reached with the bastion's defenders (Jaysh al-Islam) which will involve a combination of reconciliation and evacuation (details here).
Finally, it has become apparent that the Syrian Army is already relocating key offensive formations for a new operation against armed rebel groups in the province of Daraa and Quneitra.

The surrender negotiations were prolonged but it seems that a compromise was reached after certain activity:

Update: 2 high-ranking Jaysh al-Islam leaders suddenly killed in Damascus' Douma city, reports of assassination
By Andrew Illingworth – 01/04/2018
BEIRUT, LEBANON (2:50 P.M.) – Confirmed reports have emerged stating that two rebel commanders belonging to Jaysh al-Islam have been killed in Damascus' eastern district city of Douma.
The slain rebel leaders have been identified as Jaysh al-Islam management chief Abu Ali Idara and treasury chief Abu Omar Maliyah. At the present time, it is unclear how exactly the two militant commanders died.
In an official statement, Jaysh al-Islam claimed they were killed in a Syrian Army artillery strike, however local opposition sources are claiming they were assassinated by their own ranks.