General Port Man Duration Question in Relation to Coupons

“The effect of cash being released will lengthen the duration of our benchmark, causing our funds’ relative duration to appear shorter”

Does this statement make sense to anyone? To put some context around the statement, the cash being referred to is in relation to coupons about to go ex-div.

I’m not sure what they mean by cas being released.

Do you have a volume # and page # for this quote?