Enquiry on the migration path for ILE holders

I hope you can help, it's an unusual situation. If a UK husband and foreign wife are married for 4+ years, the wife receives ILE from the consulate. Indefinite Leave to Enter.

If there is a divorce before the ILR period is completed, is there still an oppurtunity to apply for ILR based upon the prior ILE? If so, is the residence period still 3 years? Or does it change to 5 years?

Thanks!