When you deposited BTC in a silk road wallet , they were transferred into the tumbler within a few minutes. After that the bitcoins would bounce around in the tumbler until they went out to a vendor. Some folks have said that the FBI somehow disabled the tumbler a short time before seizing the site so I guess its possible that if you sent bitcoins in shortly before the end of the road they might still be in the wallet you sent them too , which is controlled by the FBI.