PIED can and is a serious problem to have. Do be careful on this.
As DLD said, why stop? Most will reduce the intensity during a light break just to keep the tissues loaded with blood and malleable as you come back into the routines. But by increasing the intensities while holding those intensities for a longer time period per repetition, the stress loading will open avenue to breaking through the plateaus.
Since you only use the extender, it's a static tension against your tissues. What DLD suggested is to break through with a high intensity load, say 4kg for 30 minutes, or even 5kg based on where you are for 20 minutes, and reduce back to 1.1 or 1.2kg for the rest of the wear time. However, wearing it alone is not enough. A stretching routine should be added to loosen up the tissues around the entire penis so the tissues can effectively be stretched. Let us know of your routines first, not just you put on the extender and forget about the rest.
Yes brother. Do stop. It will harm you in the long run.
Yes. You can increase the tension in short burst, and reduce to lower tension below 1.1kg for the long wear time.