Defending champions Worcestershire Rapids re-sign New Zealand batsman Martin Guptill for this year's T20 Blast.
Warwickshire are to play their Championship game against Essex in July at the home of rivals Worcestershire.
Worcestershire promote Alex Gidman to first-team coach, as Kevin Sharp takes on backroom role.
The England & Wales Cricket Board confirm their new competition in 2020 will be 100 balls a side - made up of ten 10-ball overs.
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Worcestershire Rapids progressed to the final of the T20 Vitality Blast series after beating Lancashire by 20 runs after a stunning over from Pat Brown where he took three of his four wickets
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