Hello
Thank you for posting your query at DoctorSpring.com
So much of a variation is sometimes normal.
Give yourself 6 months or so, after stopping birth control, for your cycles to stabilize.
So they should be fine from October onwards.
Meanwhile many factors can impact the menstrual cycle - stress, anxiety, emotional turbulence, weight changes, travelling, smoking, late nights, erratic eating.
What is your age ?
Have you got your thyroid levels checked ?
Looking forward to hearing from you.
Take care,
Regards.