After naming chief technology officer Hans Vestberg next in line as CEO, Verizon announced that top operations exec John Stratton is resigning from his current role and will leave the company by the end of the year.

Stratton, 57, is exiting Verizon after more than 25 years at the telco and predecessor company Bell Atlantic Mobile. Most recently, he was EVP and president of global operations.

Lowell McAdam will retire as Verizon’s CEO effective Aug. 1, when Vestberg takes the reins. “Effective immediately, Stratton will step down from his current role and will support a smooth transition as a strategic adviser reporting to Lowell McAdam,” Verizon said in a statement Friday.

Swedish-native Vestberg is the former CEO of Ericsson who joined Verizon in April 2017 as CTO and EVP/president of global networks. He was ousted by Ericsson in 2016 after a string of missing quarterly financial targets.

The reshuffling of Verizon’s top ranks comes just months after another high-profile exit: Marni Walden, EVP and president of global media, stepped down at the end of 2017. During her run at Verizon, she had been the key architect of the company’s acquisition of Yahoo and the formation of Oath, which merged AOL and Yahoo.