The way I have read the white paper is a process in which the POW "lite" tokens that have been airdropped are held at the moment in an Ethereum account (each day) as POW (ERC20) compliant. This is so they are not traded, yet.
http://powtoken.com/POW_Whitepaper_19_09_2017.pdf
Before they are setup to trade as POW they will setup a means of trading through Facebook some POW "lite" between users, this is to get them used to the process.
Once the Airdrops are completed (Facebook, Twitter etc...) the current POW "lite" will be converted to POW as a 1:1 ratio.
Holders will need to convert as all POW "lite" will cease to operate?
Users will send their POW "lite" to the Ether Address for conversion to POW which is now trade able across exchanges.
The current powtoken.com site will close.
I am certainly wishing this to be the case though I could have read through wishful eyes
Edit - From white paper
we will build a ‘bridge’ so that owners of POW
‘lite’ can transfer their holdings out of the POWtoken.com account and into the Ethereum
Blockchain, making POW ‘lite’ fungible with the ERC20 POW
