Moscow is ahead of the curve
The threat of expanding anti-Russian sanctions influenced Russia's decision to start getting rid of American bonds.
Economic experts surveyed by Russian media come to this conclusion.

Thus, Ivan Antropov, First Deputy Director of the Institute of Contemporary Economics, whose opinion is quoted by Moskovsky Komsomolets , points out that the Central Bank previously persistently increased its investments in American bonds, despite sanctions, because American securities are very liquid – they are easy to buy and easy to sell.
“The desire to increase the return on assets cannot justify the sale of American bonds: such operations only bring losses to the Central Bank. Therefore, the sale of American bonds may mean that clouds are gathering even stronger around Russia, although no one has advertised this publicly yet. Probably, anti-Russian sanctions are now being prepared that will make all previous ones pale in comparison, and a very tangible risk has arisen of losing existing investments. So the Central Bank played ahead of the curve,” believes Antropov.
In turn, Yaroslav Lissovolik, chief economist at the Eurasian Development Bank, told Rossiyskaya Gazeta that the April sanctions and the threat of their expansion could have played a role in the "dumping" of US government bonds. However, he also noted that the reduction in dollar assets in reserves fits into a long-term trend of diversifying them through gold and obligations in euros and other currencies.
According to him, the role of the yuan, recently included in the basket of reserve currencies, is gradually growing, and the emergence of other attractive alternatives is not excluded.

“Russia's investments in US government debt have fluctuated greatly since the introduction of sanctions. So, in January 2014 they amounted to almost 132 billion dollars, in March they fell to 100 billion, and in April 2015 they reached 66,5 billion. Then the Bank of Russia again began to increase investments in treasury bonds, and in April 2017 they exceeded $100 billion,” RG draws attention to the dynamics of Russian investments in American securities.
Moscow is playing ahead of the curve.