Yeah so I found that as soon as you find that cell standby draining restart or turn off and on your phone, it worked for me from like 4hours to few days and I know maybe not a perfect solution but hey it works
Yeah so on new update (12.5.1) i have cell standby problem again, and it drains like crazy, also my data is randomly disconnecting together with Bluetooth like lagging for 10 sec and then it goes back to normal, something that haven't happened before