Got code P0130 O2 Sensor Circuit Malfunction (Bank 1 Sensor 1),
I have about 106k
Passenger side cat done last month and driver side covered under warrenty a couple years back.
I know im in need of new 02 sensors.
My question is- Is it front or rear 02 thats just before the cat curves I should be ordering?
and should I act quickly or is some thing bad going to happen

Or anything else I should be looking for??