I have a private account on New Relic which is set up to monitor our company's internal app. I am also an admin on our company's account with two sub-accounts with different subscription plans. I need to transfer applications and servers from my private account to one of company sub-accounts. It's possible to create a new application for a desired account and change API token in application's New Relic config, but this will lead to losing all history and stuff, changing tokens for this particular app and its servers, which I don't want to happen.
Is it possible to transfer application/server from private account to another account/sub-account via application settings on the New Relic website, or do I need to contact their support to help me with that?
Unfortunately New Relic is unable to move data between different accounts.
In this case as you mentioned your best bet is going to be to update the license key so that the applications are reporting to the new account. You will not have the historical data but you can keep the application around on the other account to view the historical data until it ages out.