My experience,

You get leveling for any carry over trip if you have a reserve line that month. In May I have a week of carryover from my April regular line. I will bid reserve in May and start the month with 33 hours of leveling.

I do not now about the C-I -C days that I am assuming you are going to make up. I have never done that so I dont know if you are leveled. Looks like I will find out in May.