Unexpected behavior of EAGLE layout editor

Question

The problem I have is described in the attached images (they are zoom-able).

I have a finalized, fully routed design:

At some point I decided to add a new gate to the schematic, so I copy IC5 and paste it as IC9. Please note that no connections on IC9 have been made yet:

Simply placing this gate on schematic causes significant changes on the board. As you can see, multiple nets become ripped up, even the nets that have nothing to do with IC5 or IC9.

Is it possible to avoid this effect?

Thank you,

Sergey

SMD111 · Answer

No thanks for "blatantly" obnoxious response, but I owe you a reply. In what sense is that "fully routed"? In that sense that is shown on the first picture. This board has been in production for years. The tiny schematic fragment Oh, would you want to see the entire schematic? Bummer, it is proprietary! clearly shows C5 connected to the power pins of two ICs but on that board it's only connected to a jumper. It's blatantly not complete. C5 is connected to inner power supply layers, FYI. No changes to the board, no nets ripped up, merely the airwires have been turned on. The rip up procedure converts a routed trace to an airwire. If you can't see the difference between the first and the second board pictures, please don't bother polluting this forum. Yes, by starting with an actually completely routed board. It looks like you are also unfamiliar with the term "routing"