Oldblue

Man, I had one of those, a great device for a quick setup for drum brakes, but that way back when I used to run 11 x 3 inch cop car drums on all four corners of my 67 Plymouth .
Satellite.

That might be in the bottom drawer of my tool chest. (Read in junk drawer)

prod

Check the front brake lines, a panic stop can over stress them and cause them to become weak and swell close to the caliper. That would cause a softer pedal.

DrLoch

I'm assuming you mean brake hoses

prod

Yup, I meant the rubber hoses going from the hard lines to the calipers.
Sometimes you can see them bulging at the end.

Blue_SS

or... if there was air in the HCU portion of the ABS module, it could explain it.

The electronic bleed might just need to be done again. When I used to to do low-level motorsports(different vehicle with ABS), this was not unusual. If the system is opened, air gets in, and it can go to the ABS module. 1 panic stop and it goes out into the previously good system.

I had the good fortune of regularly braking hard, so this surfaced fast... lol

It's an idea, at the least. Hope it helps.

If I bleed brakes, I always exercise the ABS. Some electronic units don't.