@IvanSidorenko1 reports (22 minutes ago) heavy Syrian army traffic to Manbij in northern Syria seemingly without opposition. Manbij currently held by US-backed SDF - see map in next tweet.
2/ Manbij is held by SDF east of Euphrates. It controls main highway parallel to Turkish border. Control of Manbij cuts off potential advance by Turkish-backed jihadists (blue color). Syrian army also massing at Deir Ezzor, where highway gives straight run to Hasakah.
3/ Syrian army has long maintained a strategic toehold in NE Syria at Qamishlo. This will presumably come into play when reinforced from troops now in Deir Ezzor.
4/ there's a very small land area on east bank of Euphrates valley in southeast Syria still held by ISIS, which US-backed SDF wasn't very interested in fighting. It will be mopped up by Syrian elite Tiger Forces.
5/ important that SDF is already co-operating at Manbij with Syrian army against potential invasion by Turkey and their jihadist mercenaries (often AlQaeda allied) prior to more formal agreement. To extent that legitimate US concern is about AlQaeda/ISIS, all very positive
