Unless clearly specified otherwise, financial instruments, which are based on future contracts, have start and expiration dates.
These future instruments are in ‘close only’ mode when there is one (1) day left to the expiration, meaning investors are no longer able to place new trades on the current contract and they can only close it.
A new future instrument is open to trade just one (1) week before the expiration date of the current investment instrument. And investors are able to open positions in this futures contract.