I don't think that's accurate.
Maybe a small handful were refurbished and that's about it.
Most of the U2's are in their original condition with exceptions of some minor interior upgrades. They still have the original Calgary 88 Olympics decal on them!
Before the Series 8s where purchased Bombardier came to town to check out the cars and see what they to do with them as the Edmonton cars for being refurbished.
The Calgary cars were too far gone then the Edmonton cars. I believe the price quote came in at over 2 million dollars a car and would not improve reliability it was more of a cosmetic refurb and would pose a shortage on cars and cause issues with service as they would be rebuilt.
The idea was ditched 38 SD160s were purchased and the decision was made to eventually decommission the U2 cars with the Series 9 cars.
Originally 20 series 9 cars were purchased for the U2 replacements but I'm pretty sure we seen more than 20 U2 cars get decommissioned in recent times.