For a specific case like that, I can't give you an answer today. We would be glad to come back to you with answers.
In general, you lapse money because either projects are not completed or, in the case of our department, we don't receive receipts to pay. That typically results in money lapsing.
I know they work hard to spend their money on an annual basis, but I'm not aware of a lot of lapses in CMHC's funding.