Well,we can say we saw this coming. Right after Galaxy On7 got Android 6.0, it was to be released for the Galaxy On5 too. And today, that happens, the Marshmallow update for Galaxy On5 is here, beginning with India with build no. G550FYXXU1BPF9.
There is no changelog available for the Android 6.0 PF9 update right now because we’re yet to see it as an OTA on a device. Rather, a firmware with build 6.0.1 is now available for Galaxy On5, signalling the release of Marshmallow update for the device.
Anyway, we could see it on a device anytime now. If you own a Galaxy On5, it’s about time you browsed to device’s settings, and looked for a system update.
If you see the OF9 update available, then be ready to grab it, it’s Marshmallow. If you see any other update, then install that too because it may be a requirement — base update — for Android 6.0 one.