Bouchier, who turned 24 this week, has played 14 T20Is since making her debut in September 2021 – including all five matches at the Commonwealth Games – but missed out on a central contract and was left out of the initial 15-player squad for the five-match T20I series.
But she has now been added to the squad as replacement for the injured Capsey, with Alice Davidson-Richards also drafted into the T20I set-up. She had initially been due to fly home after the third ODI in Antigua on Friday.
England took an unassailable 2-0 lead in the ODI series on Tuesday night with another crushing win. Coincidentally, they have won both games by 142 runs. The first T20I will be played in Antigua on Sunday, before four more fixtures in Barbados on December 14, 17, 18 and 22.
England T20I squad: Heather Knight (capt), Lauren Bell, Maia Bouchier, Katherine Brunt, Alice Davidson-Richards, Freya Davies, Charlie Dean, Sophia Dunkley, Sophie Ecclestone, Sarah Glenn, Amy Jones (wk), Freya Kemp, Nat Sciver, Lauren Winfield-Hill, Issy Wong, Danni Wyatt
Source: ESPN Crickinfo