There is a particular instance where you can use in the platform in the way you suggest, when there are technical changes done in the structure or system of that platform. On the platform suggests that it is up and running and something occurs on it, as we say that something occurs online.

Is it on the platform or at the platform?

You can say either. You stand on the platform and you wait on the platform (though you could also say you wait at the platform). The train arrives at the platform. (In the UK, the announcements refer to "the train now standing at platform 7".)

How do you use platform in a sentence?

Examples of platform in a Sentence

He stepped up onto the platform and looked out into the audience. She stepped off the train onto the platform. Our train is boarding on platform 6. The party adopted a new platform.