Yes, if you are using the pet meter, then the numbers that people mention here would differ by I think around 50 points.
So, the people who use human meters say the cat gets a decrease for 50 and under.... that means on a pet meter, you would decrease the dose when you get a number that's under 100.
You will save yourself alot of money if you switch to a human meter. If you are in the US, check the price of test strips for the Relion meters and compare it to what you are paying for the test strips for the pet meter.
On your ss, if you switch to a human meter, leave a blank line and add a note on that line to say switching from pet meter to human meter.... that way, people will not be puzzled by the change in your numbers. You will be getting lower numbers on the human meter and without a comment, people will think you are doing much better on the insulin.
And again, once a day is not good for cats..... maybe for dogs, but not for cats.
ETA: since you are getting numbers that earn a decrease in dose, you could drop to the 2.75u again. And, if you are still getting numbers under 90 after giving the new dose time to settle and clear any bounce, then decrease again to 2.5u.