When futures contracts are long, only 12 contracts can appear at the same time, and subsequent contracts will be changed in turn. Therefore, the purchase contract can only be held for 1 1 month at most (speculators must close their positions one month in advance). For example, if you bought the contract of 090 1 on June 2008+0/,you must close the position or move the position before June 2008+February 2008 +3 1, otherwise the system will close the position (enterprise hedging customers can hold it until the last trading day). If you want to keep it, then you must move your position. As for what you said, the price you bought at that time was low, which may increase the cost after moving the warehouse. This is caused by the basis difference, but it does not affect your investment plan. Basis will only affect your rate of return, not your judgment on the trend. It is normal that the trend of 12 contracts of the same variety is the same, and there must be a price difference between the contracts. There is no need to worry too much about making long-term investments. A little further, we should talk about the knowledge of forward market and reverse market, as well as basis arbitrage. It's a long story, so I won't say much here. You can find some related books to learn more about it. In short, if you want to make a long-term investment, the basis will not have much influence on your actions.