The pair, who each have lucrative IPL deals, were not initially expected to arrive on the tour until after the completion of this weekend's three-day warm-up match against Derbyshire.
But McCullum, who has played just once for the Kolkata Knight Riders, and Taylor, who represents Pune Warriors, will now have more time to get used to English conditions ahead of the two-match Test series.
McCullum is due to link up with the team during their training session in Derby on Friday, with Taylor following within 48 hours.
A Cricket New Zealand spokesman said: "Black Caps captain Brendon McCullum and star batsman Ross Taylor have been released early from their Indian Premier League teams.
"McCullum will join the team in Derby later tomorrow and Taylor is expected to arrive over the weekend."
- Sports & Recreation
- Ross Taylor
- Kolkata Knight Riders