v16.1 - "Strip Guids" - has that changed recently?

[Paolo F Cantoni]

In the past, we used a technique of creating a Tag Value that corresponded to the current GUID of the item (i.e. vertex, arc etc.).  We then exported the package with the  Item and Tag having the same value.  Thus, when we imported the package with the [X] Strip Guids marked, the item would "remember" where it came from - because the tag was not changed!  We've just done a large import (twice because we thought we'd made an error), and we find that the tag value is also updated!

When did this change come about?  Can it be suppressed?

Reported,
Paolo