I've taken up to 10g/day of potassium in bicarbonate and citrate forms without issue. My serum K levels are always normal. I'm not suggesting others do this, but if your kidneys function well, they will excrete excess potassium. My dose of potassium usually ranges in the 1-4g/day. I've had many years taking 4 g/day. Potassium can be deleterious if it builds up in your system.
For me, magnesium is more important than potassium. Keeping mag at bowel tolerance is more effective, for me, than potassium.
Dr. Moore, in his book The High Blood Pressure Solution: <[
www.amazon.com] addresses potassium fears starting on p 316 (you can click on "look inside" and search on "extrarenal." He also notes it can take the body a few days to adjust to increased potassium intake using both renal and extrarenal mechanisms.
Testing with a Cardymeter, as Ron suggests, is the most precise way to go about it. You can also slowly increase your potassium intake and note whether your PVC's improve.
George