If you have started an application (completed the candidate questionnaire), send your 6 semester transcripts as soon as they are complete (beginning of summer break). This will require coordination on your part with your counselor, and maybe a little leg work to get the mailing address/school code. West Point only accepts electronic transcripts from certain (Parchment, I believe) providers. Otherwise, you need to have your counselor send them. This lets you get ahead of the process even if your main application doesn't open until later in the summer.