You should follow your plan with determination and rigour. The intention of this is not to make you a slave to your own schedule (remember, you are writing your own schedule); the intention is that you will put into action the strategies that you planned at the start of the year, and that you will achieve the goals that you set at the start of the year.
Your Yearly Plan is, in effect, a letter that you wrote to a future you; a message from a calmer time - a reminder of what is really important.