Can you help me cycle/zig zag my calories?

Well there are a few questions that need to be asked before making any recommendations:
1) What is your weekly weight loss goal set to?
2) Are you eating a clean diet or is there some junk in it?
3) By toning do you mean fat loss or muscle building as they are 2 goals which should be separated in my opinion.
4) Were you eating back the exercise cals when you plateaued or just eating 1200 net a day?

Eating back means that the net cals are equal to your daily goal. Ok so with that answered then your goal should not necessarily be to shed weight, as effective muscle building requires a surplus of cals now also keep in mind that the scale weight is not what we want to pay attention to but body composition which means you can shed fat while gaining muscle but the main goal is to build muscle. So here is what you need to put your goals towards meaning that you want to eat about 100- 200 additional cals above maintenance but you should try to eat 1.25 grams of protein for every pound of lean bodymass per day. The reason I separate fat loss and muscle building is that to do one you can not really be effective in the other unless you are obese (the body can pull the cals from fat needed for muscle building, which it does not do as effectively when you are lower bodyfat %) So with that in mind turn your goals towards muscle building and if you gain more fat then you can easily switch back to a weight loss phase post muscle building. I am currently attempting to cut to 10% bodyfat. I am not far off that goal right now using the cycle method on and off during this phase to preserve muscle mass and shed the fat. Once I have hit that goal I am doing 2 weeks at maintenance to determine my exact requirements to maintain (this will most likely be above mfp numbers) Once I have stabilized I am going into surplus to build muscle but the training program will compliment my diet which will still be clean and the same types of foods but more protein and a set program.

Now if you wish to cut bodyfat then the cycle you suggested should work give it a shot for 2 weeks and see what the results are, the only way to truly tell how many cals the body needs may be to add more if plateaued. I have helped many friends break plateaus by eating more and altering to a cleaner diet. The most extreme was getting one friend to increase her daily intake an additional 500/day to break her plateau and get her losing again as she was simply not eating enough at 1200 a day net to keep her fat loss moving, for effective fat loss she needed 1700/day.

120 @ 17% bodyfat is 20.4 pounds of fat and 99.6 lean bodymass meaning 100 grams of protein a day to build muscle more effectively.

you can get your true lean muscle mass percentage electronically tested at many chiropractic offices. 17% body fat is pretty low for a female, and may actually do more harm than good over the long haul . . . but I will not lecture on that topic.

In any event, it sounds like you're eating a healthy amount of calories and the mix seems appropriate.

For building muscle mass of course you want to do strength training interspersed with cardio. An excellent way to do this is cycling; specifically long, steady climbs. Not sure where you live--but if the geography is right, you may want to consider taking a look at how you can work longer, progressive climbs into your current rides (maybe you already do this?).

Anyway, best of luck in achieving your goals.