I don't know a specific date as there is virtually no information from a Russian perspective on these deployments with info from western source in the context of defence measures against Russian aggression since the Georgia conflict as there have been about 6 separate NATO exercises with NATO and EU forces in the first few months of Obama’s presidency.
I am estimating based on the preparation for the next Reagan administration from the Brzezinski/Carter regime with there pre-arranged large scale operation in Afghanistan in 79 I would predict a year or maybe before the end of this year that a staged incident either in the Crimea, Georgia or the Baltic’s which a false flag terrorist attack as a likely scenario which they will blame on Russia as the FSB staging it in which in conjunction with there sleeper cell Islamist forces could launch an attack in Russia but it will not be like Barbarossa a psychical assault by a huge invasion force .
A declassified 1998 Defence Intelligence Agency (DIA) Intelligence Information Report (IIR) of foreign terrorists networks in Russia and the Crimea and central Asia from Afghanistan and Pakistan through Turkey and Azerbaijan from a 2000 Freedom of Information act request from Judicial Watch states OBL/Khattabs network in Russia and sleeper units to carry out terrorist/sabotage/espionage in Russia for future events to rely on an economic crisis situation as a catalyst for recruitment and action. As note in the report the man responsible for the transfer of militants and training in Turkish military bases is Sakka which is revealed in a court case in Turkey to have trained the 9/11 hijackers to originally fight in Chechnya.
A good deal of information concerning OBLs and al Qaedas efforts in Chechnya, the Caucuses, Crimea, and the Central Asian Republics is covered in the IIR. The confirmed existence of a [secure, reliable, terrorist-sponsored] direct route to Chechnya from Pakistan and Afghanistan through Turkey and Azerbaijan is a stunning information point within this IIR especially in light of the date of the information, 1998.
http://www.judicialwatch.org/story/2004/nov/defense-intelligence-report-details-al-qaedas-plans-russia-chechnya-and-wmd
http://www.judicialwatch.org/cases/102/dia.pdf
http://original.antiwar.com/justin/2008/01/07/nukes-spooks-and-the-specter-of-911/
http://www.timesonline.co.uk/tol/news/world/europe/article2936761.ece
I believe that the missile shield is probably for the purpose of the integration of HAARP weather technology which will be used in the assault and that the strange light phenomenon over Romania, Moscow and China (although I can’t find the video for that one).
Yugoslavia is the model and test case for aggression against Russia.
Not only are the same Islamic networks and countries involved but also the same in intelligence front NGO’s (NED, USAID, Soros, etc), but the same hyper inflated death toll which changes depending on the source 100,000, 100,000-200,000, 250,000 and as high as 500,000, ludicrous rape number of 30,000 and even the narrative is the same Milosevic Communist authoritarian leader supporting nationalism and separatism in ethnic enclaves of Serbs in Croatia, Bosnia and Kosovo
You will also note that Obama’s staff is almost entirely made up of people involved in supporting Islamic terrorism as far back as 79 in Afghanistan (Brzezinski and Gates) and Clintons destruction of Yugoslavia (Holbrooke, Albright, General Jones, etc).