I'm leaving next week, so I got covered by this new law.
What the HR department did was the calculations of the compulsory part of the pension fund according to the law, and then the variance to what I'd actually been deducted. The compulsory part needs (now) to stay in switzerland, in a "Vested benefits account" at a bank, and the rest is returned to my normal bank account.
I'll try to find the link to the official leaflet they gave me, it's quite helpful.
Oh, right, the 1st pillar, nope, it needs to stay here as well, and your colleague can't forget to let everybody know of their new address (and any subsequent changes), so that when they reach retirement age, the swiss government can send them their pension