I have three opinions about your post,
First, to your comment,
Second, to the length discrepancy,
I believe you are reading too many audio forums :-)
Third,
With two dedicated 20A lines, you will be further along than most here so don't sweat the length difference . My only suggestion on this issue would be to consider whether you would ever need three dedicated lines before you put the ceiling in.
First, to your comment,
The cables are resting on the bracings of my ceiling which will then be covered.I am not an electrician, and hopefully somebody here that is can weigh in, but I believe electrical cables (i.e., Romex) is required to be fastened to the floor joists and not "resting" on anything. Hopefully, an electrician performed the work, and your comment above is simply a figure of speech. If not, I suggest an electrician look at things before you cover up the area with a ceiling.
Second, to the length discrepancy,
I believe you are reading too many audio forums :-)
Third,
With two dedicated 20A lines, you will be further along than most here so don't sweat the length difference . My only suggestion on this issue would be to consider whether you would ever need three dedicated lines before you put the ceiling in.