You can use the auto_update_core parameter when creating/updating profiles in order to specify if your browser profiles will update automatically as soon as new cores are released. It can be used in the Start Quick Profile, Profile Create, and Profile Update endpoints. 

• Enable automatic updates (default): If auto_update_core is true, the profile will automatically update to the latest core version

"auto_update_core": true,

• Disable automatic updates: Set auto_update_core to false and specify the required core_version

"core_version": 130,
"auto_update_core": false,

Consider the following while using this feature:

• If the parameter auto_update_core is left unspecified when using the Profile Update endpoint, it will reset back to true, its default state
• If you want to keep your current core version, you must ensure that the auto_update_core flag is set to false, preventing it from being automatically updated
• When updating a profile, changing the core version to anything other than the latest version is not supported
• We recommend using the default settings, which ensure your browser cores stay up-to-date – Multilogin is not responsible for any bans or detection issues if profiles are using an outdated core version