Nut, you are interchanging some confusing (to me, at least) terminology in subsequent posts - from my understanding, it appears that you would like to trade serial calendar months in the futures contract ES; in other words, you would like to 'leg' in to and out of one month code contract versus another month code contract in the same name. For example, March 11 ES future against a June 11 ES future.
If that is indeed the case, you can do it within the same account, and as fast as you can manage. Many traders do it with automation - for example, make markets in the June 11 ES and when work to fill the hedge with the March 11 ES. You can also use the exchange supported implied calendar spread market to offset your position.
If you choose to do this, be mindful of the Globex message-to-fill ratio policy.
If that isn't what your original OP intent was, then never mind.
If that is indeed the case, you can do it within the same account, and as fast as you can manage. Many traders do it with automation - for example, make markets in the June 11 ES and when work to fill the hedge with the March 11 ES. You can also use the exchange supported implied calendar spread market to offset your position.
If you choose to do this, be mindful of the Globex message-to-fill ratio policy.
If that isn't what your original OP intent was, then never mind.