Twitter has reversed changes

There have been concerns over the rise in the number of cases of trolling on Twitter

The changes allowed blocked users to continue to see tweets and interact with accounts that had blocked them, leading to an outcry.
Twitter said it was reverting to old rules, under which users are not able to follow an account once blocked.
Blocking is used by people to stop trolls and rude online commentators from interacting with them.
"We have decided to revert the change after receiving feedback from many users - we never want to introduce features at the cost of users feeling less safe," Michael Sippey, Twitter's vice-president of product, said in a blogpost.
"Any blocks you had previously instituted are still in effect."
Source : BBC News