I agree - a great result!
IMHO 5.6 to 5.7 is no big deal and much better than most can manage so you should be very happy.
I'm a statin refuser and don't accept the cholesterol hypothesis but I'm still interested in what you or your doc thinks may have caused the increase.
Has your diet changed significantly, maybe low carbing with lots of fats? Even if it has that seems like a big jump even for the diet theory (usually only 10-15% change due to diet if I remeber correctly)?
Have you lost a lot of weight? Another theory says that this sometimes temporarily raises cholesterol levels (again though, I don't think by this much.
I'm interested because mine went up when my HbA1c came down and I couldn't come up with any reason, despite a lot of reading here and elsewhere.