The total size of the update is 900MB and thus it is advisable to download it via a Wi-Fi network. They should also connect the device to a charger to ensure that the upgradation process does not stop mid-way due to lack of charge in the device.
Reports are also coming in which suggest that another carrier- Verizon, is also rolling out the Android M update for the S5.
Along with the new OS, the update will also contain some security upgrades and some bugs and error fixes.
As for other carriers like AT&T, US Cellular, and T-Mobile, no specific information is available as to when the update will be rolled out. However, rumors suggest that it might happen in the ongoing month itself.
The update is also being rolled out by Samsung in South Korea for the S5. Here too, it has been released OTA and users will receive update notifications when their devices are ready to receive the update. They can also manually check for the update by heading over to Settings>About phone> System updates.
Android Marshmallow will bring features like Doze mode and Google Now on Tap to the Samsung Galaxy S5.
Stay tuned for more update on Samsung Galaxy S5.