Unless your owners manual calls for a specific breaking oil, and specifies a breaking period, (which is rare today), you can switch anytime you like.
Check the spec's for your motor oil. Lubricity is basically the same now for both, mineral oil, and synthetic oil. That means the engine won't break any different, with either one. This is why engines now often come from the factory with synthetic oil in them.
If it was important for you to wait, you would not need to ask this question, your manual would specify that.
If you choose to believe incorrect, outdated thinking, which tells you otherwise, you can wait, and switch later. That won't matter either.
It's 2016, it's all just oil now. The only difference is, synthetic works better in extreme temperatures, and allows for longer drain intervals.