eBay will start implementing Store changes in May 2018. The main reasons eBay are making these changes are to improve search engine optimization, mobile optimization, and better site security.
eBay will be making these changes for each Stores user. There is nothing that you need to do to get the updated version of eBay Store, although, the earlier policy changes now apply to Stores.
This means you can't have contact details (such as phone numbers, email addresses, physical addresses) or links directing users off eBay (such as personal websites or social media).
If you wish to read more about these restrictions you can catch up on the recent seller release policy changes in this article here.