Although Freckles has never earned a reduction, I feel confident in answering this question but if other more experienced folk want to chime in, that's great.
I'm afraid I'm still confused; the TR guidelines advises to wait until we see numbers under 100 for an entire week before attempting a reduction. However, it also says that if the kitty drops below 50, to reduce the dose by .25 units. Which is it?
It's both. Some kitties will coast along at 80, 65, 70 etc (numbers below 100) for a week(s) but never make it below 50. So if they are below 100 for a week they get a reduction.
If a cat drops below 50, that's an indication that the insulin dose may be too high and it needs to be knocked back a bit so you reduce by .25u. As Marje's thread indicates, it's important to try and catch these lows (test often) to keep your cat safe.
It also talks about cats with "high dose conditions" and the need to reduce in whole units. What are considered "high dose conditions"?
Good question. When a cat keeps requiring more and more insulin (it looks like the insulin is not having the effect that it should - like my Freckles) the caregiver increases the dose. So once a cat gets to about 5-6.0 u, instead of increasing by .25, which if you look at is percentage wise, is actually quite a small dose increase, you need to increase more than .25u (.5u instead of .25 u increase). If the cat is up even higher and receiving say 10u of insulin, increases would be higher too. So when increases get higher, I would imagine so would the decreases (but like I said before, my cat has not earned a reduction yet, so I can't speak from experience). Because I posted frequently throughout this diabetic journey, the experienced people were able to get to know Freckles more and as I approached higher numbers, they were there to offer support and advice all the time - which is really appreciated.
I guess I am not sure what to do when.
You aren't alone here. That's why it is so important to post your questions, read other threads and see what the advice is for other people so a person kind of 'gets the hang' of the diabetes 'dance'. Looking at other people's spreadsheets and seeing what they did and asking them questions is also a valuable learning experience. When you aren't sure of something, are in a dilemma, feel you know what to do but just want to double check, you are strongly encouraged to post and ask for help/guidance.