YOu are almost there but are not reporting the overnite test correctly.
Did you make your last FC test at least an hour after your last FC addition? If so, then your OK. If not, test again tonight an hour after your last addition and then tomorrow AM and report back.
Again, you may have done it correctly by waiting one hour before the test but I couldn't tell from your post.
The granular CYA is a lot cheaper and is just as effective. It simply doesn't show up on the test as quickly. I'd save some money and keep the granular but that's your call.
You are very, very close to completing the conversion. YOu will be done when.....
1. Your pool water is sparkling
2. Your CC's are .5ppm or less
3. You can hold your FC overnight without losing more than 1ppm.
So you have accomplished 1 and 3. Do you know how to do the CC's test? If so, please do that test tomorrow AM and post it with your other FC results. Then you will let your FC come down below 10ppm (on it's own) and post test results for pH and CH....We know your CYA is zero (so don't test for it) and we hope your CC's are .5ppm or less.