<p>Well if you are ‘rather good at it’ then this probably won’t help you, but you can sign up for Harvard’s intro CS course online at any time and finish by the end of the year:</p>
<p><a href=“CS50's Introduction to Computer Science”>https://www.edx.org/course/harvardx/harvardx-cs50x-introduction-computer-1022</a></p>
<p>But I don’t totally understand what is really driving this question. Are you concerned with finding the time? Do you actually need more instruction? Or is it more that you want to take CS classes so they are on your transcript but can’t fit them in?</p>
<p>If you are already ‘rather good’ at CS, then just do it. I don’t see the issue.</p>
<p>There are lots of great CS courses online at edX, Coursera, etc.</p>