ISO 13485 Records Retention Requirements

Re: record retention

In FDA regulations, it is mentioned that records has to be retained till the "expected life time of the device" which is engineering calculations. the same we mentioned in our QMS manual, procedure. But if the product is working after the expected life time of the product with some servicing/changing parts, then how to mention the retention period of the records?

example:
defined expected life of the product: 5 years
in the manual/procedure mentioned that record retention is 5 years
product age in use: 6 years

in this case i've to revise the manuals and all frequently if i found that device is still in use..?

According to the current requirements of FDA, Canada, EU and ISO13485 what would be the best retention period to be established for medical device records with SL 3 years, to cover all requirements?

What would be record retention of device without shell life, that was subsequently rebranded and shelf life added to device?

This would be a device that was sold by prescription only in which distribution was discontinued in 2010.
Procedure to keep obsolete devices minimum of 15 years or is this too excessive.

How do you deal with entities who are re-selling the device no longer distributed and are selling without distributor approval on internet, note that already have reported unlawful sale to FDA?