Cumulative months between dates

Here's a tricky one.

I have three columns: A, B, C

A is a start date
B is an end date
C is the date in which a certain number of months has been reached.

For example:

A1) 1-22-90
B1) 6-29-96
C1) Date in which 53 months has been reached.

I need to find three different "checks point" - 96 mo, 120 mo, 144 mo.

"What is the date in which 96 months has been reached when adding number of months between a series of separate dates"

something like that. Does this make sense? I appreciate any help I can get! Thanks!