As you can already understand from the summary, When you power an powered rail and then you move it with a piston(regular or sticky) the powered rail continues to be powered!
This also happens with detector rails!
Ps. Sorry for the pictures not being in order
Thank you for your report!
However, this issue is a Duplicate of MCPE-33886.
If you have additional information, please add it to that report.
Please search before reporting, as it's likely that one exists already.
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