The spying I am discussing is

• the bluetooth probe of nearby devices deep in firmware
• the Wifi antennae name probe of nearby wifi devices deep in firmware
• the Assisted-GPS (A-GPS) of your location within 15 feet, to locate video cameras the next day.
• the microphone transcribing speech to text legally without court order and streaming text of all people whispering near your phone
• the remote spy query of all urls you might have used that phone for, and list of cookies , but only a fool uses a burner phone for anything except feeding it money (required to go online on alcatel to do this and other burners)

A burner phone should always be used for one single purpose , for one or two sites maximum. One being google mail setup, not google mail use.
If feeling adventurous... you might use the voicemail feature of your burner phone to reveal your phone number to your colocation host of your server, after all, you already gave them the google email tied to that burner anyways. use different burner for domain registrations. use different email too.

google requires a SMS every 90 days from suspicious people.

Some say I am suspicious.