The half game rule has been passed by the RFU and will be in force next season 2019-20.
Click here for the updated FAQ on this.
Further information can be found at www.englandrugby.com/halfgame.
The RFU have a twitter handle - @agegraderugby which may help and there is also an article on the main site
https://www.englandrugby.com/news/half-game-rule-introduced-regulation/