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Time between Opening and Closing legs is usually a day or two. This is the term of the repo. If the term of the repo is overnight, it is called an overnight; everything else is called a term repo. Term repos are more complicated due to margin calls. The observed price of the security rises or falls, there may be margin calls to preserve the haircut.
Closing leg:
Some articles
Breaking News: In the week of September 16 of 2019 there was a huge problem in the repo market. On Sept 16 and 17. lenders disappeared from the market, leaving many who wanted short term funding without takers; this created a huge spike in the overnight and term rates (rates spiked to 10%, when Federal Reserves target rates are 2.0 to 2.25). The commotion was quelled only when the NY FED stepped in providing liquidity in the market. Speculation abounds as to the root cause. The main effect was that there was more demand for cash than there was supply.
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