When we got our tuxedo cat Monte from a rescue organization he was COVERED with dandruff, which worried me because I am at least mildly allergic to cat dander! He now has a beautiful coat - shiny and dandruff free -- he gets lots of compliments on it. The dandruff probably had two causes in Monte's case: stress, (the dandruff was noticeably worse after our 1 hour drive home than it was when we first put him into the car) and diet.
I bring up the stress because you mentioned that your kitty's primary caretaker has moved away -- that sort of change can be very hard on a kitty, as I am sure it is on the rest of you. She, like the rest of the household, may need some time to adjust to her new circumstances.
Also, there is one supplement I know of that you can make yourself to add to your kitty's food. We found it to make worlds of difference (this is what we added to Monte's food before completely switching him to a raw diet, which helped his coat even more). It comes from Anitra Frazier's book: The New Natural Cat. It takes a little bit of prep, a little bit of money, and a bit of research to find some of the ingredients, but it was totally worth it for us:
1 1/2 cups yeast powder (brewer's, tarula, or nutritional)
1/4 cups kelp powder or 1/4 cup trace mineral powder
1 cup lecithin granules
2 cups wheat bran
2 cups human grade bone meal, calcium lactate or clacium gluconate
mix well and store covered in the refrigerator.
add 1 tsp. of the mix to each cat's food twice per day.
Mothers Market, Whole Foods Market, and other health food chains carry most, if not all, of the ingredients.
Here is the rational behind the supplement suggestion:
Some people, Anitra Frazier included, believe that dandruff is actually a waste product that is caused by a back-up of wastes in the cat's system. (much of what follows will paraphrase Anitra) That is why improvements to diet should help -- proper diet keeps the body's systems functioning, so that waste is minimized and processed the way it should be. Also, you can try feeding the cat scheduled meals rather than leaving the food out 24/7. According to some, the smell of food stimulates the brain to prepare the body for digestion, which slows down waste disposal processes in the cat's system. Careful grooming is also important since it will help keep these waste products on the skin from building up and causing further problems.
If these people are right, then, when you have the money to do so, it is also not a bad idea to take the cat to the vet to see if there is any other underlying cause of dandruff -- it could be indicative of illness in the waste processing organs: kidneys, intestines or liver, and if related to metabolism, the thyroid.