Fantastic news numan. The low carb diet is really working well for you.
Obviously talk to your doctor as soon as possible about the new diet and any adjustments to the meds, but in the mean time I would seriously consider halving the gliclazide dose straight away and monitor it to see how it goes. Actually I would completely forgo the immediate gliclazide dose and start on the half doses whenever your next dose is due (assuming that you're keeping up the LC of course). I'd still take the metformin though.
BTW. The Metformin mainly works by helping with insulin sensitivity, so because the metformin doesn't actually stimulate more insulin or anything it is very unlikely to cause a hypo.
The Gliclazide however, stimulates your pancreas to make more insulin, so it could cause a bit of a hypo with your current BG levels - which BTW are fantastic

.
Reducing you Gliclazide requirements is actually a really positive thing. Reducing the insulin requirements (whether that be externally injected insulin or what's stimulated internally by drugs - no difference) is the best possible outcome for a T2. The less Gliclazide you need (to maintain BGL) then the easier you will find it to lose weight. If you can reduce that med and maintain good BGL control then it's a super positive outcome.