Of course, even without the phone, the scammer will always manage to stay in touch with you as that is the only way to be able to get their hands on your money.
Usually this part of the scam sees the scammer direct you to a fake company representative or perhaps a convincing website that will discuss the terms and conditions of the phone to you.
At this stage they will often refer to you as their spouse.
They will put you in touch with a superior officer to arrange the leave with you.
There may be fake contracts to fill in or documents to be sent to make it seem more official.
At this stage the scammer will insist that he is unable to pay for the service at this time for one of many reasons and he will ask you to pay it for him, in most cases promising to pay you back as soon as he can. The US military goes to great lengths to ensure their personnel have access to the means to communicate with their family back home wherever possible.
Further, the US Military (or other military forces for that matter) will not allow another person to apply for leave on a soldier's behalf.