I play quick play solo and I've created a Championship with the WRC from 97 to 2011.
It happened with a 96 difficulty and with a 85 difficulty.
With the 96 Championship it happened on Monte Carlo and Sweden. I did all of the Rally and on the last stage in both Rallys the AI dropped 2/3 minutes. I was losing 10/15 seconds per stage before that.
In the Championship of 85 I was winning stages with 2/3 seconds, losing some by 2/3 seconds and then, in Mexico, AI dropped 3 minutes in one stage and 2,30 on other.
I cannot say the exact stages, I did not take prints.