If it's the business version, you have full access for 30 days, admins have access for 90 days, then it's deprovisioned (source: https://support.office.com/en-us/article/What-happens-to-my-...)

On the O365 Personal/Home or direct OneDrive plans, it looks like your data remains available but read-only for 3 months, then your account is "frozen." You can do a one-time 30-day "unfreeze" to get access to download/delete (to get under your quota), then it gets "frozen" again. Eventually it'll be deleted, but I don't see documentation for how long that takes. (source: https://support.office.com/en-us/article/what-does-it-mean-w... linked from https://support.office.com/en-us/article/OneDrive-storage-pl...)