Is a 1550 superscore considered worse than a 1550 in a single sitting?

International student from the UK here. I know my chances are already slim and only around 20 students a year from the UK are admitted.

Got 1510 in my SAT in Year 12 (Junior year), 750 EBRW, 760 Math.
Got my results for my second sitting (Year 13/Senior) a couple days ago, I got 1520 overall. 720 EBRW, 800 Math.

Trouble is I haven’t been taught English in school since Year 11 due to how the UK school system works so my finer English skills have stagnated a little bit. On the flip-side I was able to prepare really well for Math and got an 800.

My superscore is therefore 1550, though. Is Harvard really going to be that bothered over me not accomplishing that in one sitting? Of course the bar is higher for internationals but I feel like my ECs (and 4 A* predictions at A-level) will be substantially more important at this point, especially with all the writing in my Common App, Harvard Supplement and in the SAT Essay being fairly high quality. I am applying SCEA, to be fair, so maybe they will care.

Thanks for your help, I’m not looking for any chances of admission but just to be put a little at ease.

Not in the least. See: https://college.harvard.edu/does-harvard-superscore-test-results

@gibby I have a 1470 (780 Math, 690 RW). If a retake and I get a 1350 (600 Math, 750 RW), that would superscore to a 1530 (780 Math, 750 RW). Would that still not look detrimental, even if my retake had a 600 Math?

Harvard used to have this FAQ on their website, but must have taken it down. I imagine it still applies.

So, no you won’t be penalized for taking the test multiple times. And, as Harvard considers your best scores in each section, it’s not detrimental for them to see lower scores in the same section from another test date. However, the more test scores you submit, the more you might appear to be a test-monkey or drone (which you want to avoid). Remember testing is only one part of the application and students with perfect test scores are rejected every year.