@350 Mag - yes, that is exactly how the system is supposed to work.
=> Expect 125-150 miles between regens for local city driving (assumes complete regen back to 0%)
=> Up to a max of 300 miles between regens if all you do is highway mileage
Ford decided to bury when your truck is in regen from the end user and your average mileage between regens.
Your active regen state, DPF Full %, average mileage between regens (green), mileage between last 5 regens (aqua), and mileage when DPF Full vs Over Limit (yellow) can be exposed via FORScan programming & monitoring:
The other DPF related PIDs not highlighted are the sensors/measures that are used to help determine when the DPF is full and to trigger an Active Regen if other conditions are met; e.g. EGTs (Exhaust Gas Temperatures above 580F)
The following FORScan monitoring display shows an Active Regen in progress:
Above is a screen capture of my best distance between regens ever, where I did a bunch of back-to-back highway trips and hit the 300 mile max on 3 of my last 5 regens. You can see here how the DPF_REGEN_% (1st column of 2nd row) is at 100% and all four (4) EGTs (Exhaust Gas Temperatures in bottom row) are near over 1000F -- this is indicative of an Active Regen in progress where the ECM dumps additional fuel after the exhaust cycle to raise the temperature of the DPF to burn off all of the diesel particulates accumulated in the DPF.
Because Ford buries all of this information, you as an owner are "driving blind" and have no idea when your truck in in Active Regen or if you have successfully completed a full Regen back down to 0% Full. All of the above is what I call the dirty & secret side of diesel vehicle ownership with all of these new emissions systems.
Good news if that you are doing primarily highway driving, so you shouldn't have any issues with DPF regen cycles
if your DPF and SCR emission systems are working as designed. I worry about to those owners who do primarily city driving (like me!) and aren't actively managing their active regens via FORScan, as these are the trucks I expect to have DPF plugging issues at some point earlier than the owner expects....