'at the same time' versus 'in the same time'

[Attila]

There are expressions like at the same time and in time and in your own time etc.

What I want to know is following:

Is there a context where the expressions in the same time could be used? (if it's correct at all)

[Tamara]

Hi Attila,

I've heard in the same flash of time,
but I don't know whether it's 'standard English' or not quite
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