Chase Checking/Savings $900 Bonus Question

I am doing the $900 bonus for checking and savings.

I had a question about the checking account - once the $300 checking bonus hits the account, can I change it from a Total Checking account to a Sapphire Checking account?

Or do I need to wait to make that change until the $200 and $400 bonuses hit after doing the 90 days in the Savings account?