To clear existing routed tracks and vias, except GND and Diff Pairs.
Altium > PCB Fliter > (IsTrack or isVia) and OnSignal and not InNet('GND') and not InAnyDifferentialPair
Altium > Delete Filtered Selection
Altium > Script > Export Specctra DSN
Electra > Open DSN
AutoRoute > Strategy > Edit Script
To Prevent Electra from Crashing . . . first strip out web page characters.
Copy and Paste the text below to Notepad before pasting in Electra !
select all nets
unselect net GND
unprotect all wires
unprotect all vias
lock net GND
protect net GND
protect all dpairs
# End My Do Tweaks
Electra > Run Do > Export Routes
Altium > Files > Import Routes
PCB Filter > Istrack and OnSignal and not InAnyDifferentialPair
Altium > Route > Retrace Selected (Shortcut Keys UC)