BLE privacy: Should address change after disconnection happens?

Question

My BLE peripheral is an advertising entity using BLE Privacy.
The advertising address(RPA) is changing every in 15 minutes.
But, when a connection is stopped and it resumes advertising, the address is not changing. 
 Should the address change when the device resumes advertising after getting disconnected?

Ulrich Myhre · Accepted Answer

Hi, 
 The spec only requires that the address change whenever T_GAP(private_addr_int) expires, and recommends that the default is 15 minutes. You are free to manually change your address on disconnection if you would like to do so, but the purpose of the Privacy feature[1] is to: 
 
 (...)make it more difficult for an
attacker to track a device over a
period of time. 
 
 So changing the address at regular intervals is enough to fulfill that requirement. 
 [1] See Core v5.0 Vol 3: Part C, 10.7 "Privacy Feature"

BLE privacy: Should address change after disconnection happens?

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