Styche indicated his desire to leave the Lambs after discussions with the club's hierarchy when he was made aware of Darlington's interest in signing him.
Darlo have submitted a bid for the player which has met Tamworth's asking price and the deal is expected to go through in the next 24 to 48 hours once Styche's personal terms have been agreed.
The 28-year-old has scored ten goals this season which has helped lift Tamworth up to tenth.
Styche joined National League Gateshead in 2016 from league rivals Macclesfield Town, and has also represented the likes of Kidderminster Harriers and Wycombe Wanderers.
His longest spell at a club was with Forest Green Rovers, who he represented 108 times, scoring 35 goals.
He signed for Tamworth in January this year.
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