The 180 day return thing is from eBay US - has not been introduced here and is not mentioned in the Spring Sellers' release.

I can only speculate about the 150 free listings, - there may not be anymore after November or some time in the future.  Ebay obviously has a long-term game.  At the moment the specials are probably making money and could be a good way to introduce people to selling that might continue in a larger scale long-term.