Deb, some people are really fortunate with getting their kitties regulated or into remission quickly but most are not. If you look at other people's spreadsheets, some have been trying to regulate their kitties for a long time. We can never know what to expect but we can learn everything possible about how our kitties react to the different dosages and the food we are feeding them. Please, don't forget the importance of the "clinical" signs with Roxy, too. Does she have a good appetite, is she urinating properly (not too much), do you see her drinking a lot of water, is she purring and affectionate with you. It is so important to see that Roxy acts like she feels well and is happy.
Personally, my Susie has been a bit of a mystery for me. I have gone up and down the dosing ladder and still don't know what to expect. What you are aiming for is up to you. Do you just want her well regulated or do you have the time and desire to try to get her into remission. That would take more risks and would require more monitoring and testing. Day and night. For me, I just want Susie well regulated. I want to find the dose that will keep her in numbers around 70 to 150 but I cannot count on that. This diabetes can be frustrating and there are no "quick fixes". Just try to relax a bit and listen to what the experts on this site say.
Roxy has come a long way and you should be proud of yourself. You may be living with this the rest of her life. Just try to find a safe dose, test her, try to get a feel of where she will go with her numbers and love her.