Leicestershire chief executive Wasim Khan is to leave the county to become managing director of the Pakistan Cricket Board.
The England & Wales Cricket Board confirm their new competition in 2020 will be 100 balls a side - made up of ten 10-ball overs.
County champions Surrey will start their defence of the title in April 2019 with a home match against Essex.
Leicestershire all-rounder Cameron Delport leaves the club midway through his contract by mutual consent.
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