I think they all have an "Inhibit" switch. My M7060 does. Per my owner's manual the ONLY time I would inhibit regeneration is because there was a compelling reason to have to postpone regeneration.So...., is parked regen selectable when the regen light in the meter first comes on? I am hearing not I think from ones that might have a similar setup.
Yes, my L3901 has an inhibit switch.
It's definitely not seamless, operator input is required.
Here is a screen shot of the relevant portion of my owner's manual:
What that is saying is that when that light in the dash comes on, the tractor has started auto regeneration, which is the way it should work, with no operator input needed. Should you be in a location where you don't want the extreme exhaust heat of the regen process right at that time, you can push the "Regeneration Inhibit" button to postpone the regeneration until you are in a safer location. For example, if you are working in an extremely flammable location and the regen light comes on, you push the "Regeneration Inhibit" button to postpone the regeneration process until you are in a safe location.
If you are in a safe location and the regen light in the dash comes on, just keep on working the tractor, don't push any buttons, and let the Auto Regeneration take place! Don't overthink this!