[1] He is part of Cricket South Africa's umpire panel for first-class matches.
[7] In January 2020, he was named as one of the sixteen umpires for the 2020 Under-19 Cricket World Cup tournament in South Africa.
[9] He was selected as one of the match officials for 2021 ICC Men's T20 World Cup.
[10] In March 2023, Holdstock and Ahsan Raza from Pakistan were inducted into the Elite Panel of ICC Umpires after Aleem Dar left the panel.
[11][12] He was one of the sixteen match officials for 2023 Cricket World Cup.