heres the crunch,
Jory seems to suggest it does alter laser power Selecting the Correct Resin Colour And Type
However you are correct in that it is a diode laser.
I am not sure where you are getting the 420nm from - the form1 (as is the case for most SLA printers) use a 405nm wavelength as far as I understand it. All of my 3rd party resins claim to be cured at 405nm.