Official visits are offerred in the summer but they occur in the fall once school starts and prior to ED deadline
You need as others have said to reach out via email to both asst and head coach of the schools that you are interested in
include gpa/sat scores top times from best strokes
ask if you can send them time drops during long course season and if they can include you in any mailings or news that they send out to their recruits
start a dialogue,if your times and grades are what they are looking for they will definitely respond
let them know you would be interested in an official visit
good luck
@TheNICKNAME – It would absolutely be OK for you to email one or more of the Ivy coaches at this time. You might say that you’re working hard and anticipating a good long course season, and state some specific goals for your best events (that are fast enough to swim for the team whose coach you’re emailing). Let them know that you’ll keep them posted and email them when your times drop.
And I absolutely love your attitude and confidence that you’re going to swim faster. Let that attitude show in your emails.