I just went ahead installed the new firmware and then did a test print with filament sensor on. I’m pleased to say we have a winner! There was no error, and the filament sensor worked as it supposed to after I snipped the filament and let it run through to trigger.
Thank you so very much for all your help with this - it is greatly appreciated!!
I will do a test with M119 and get back to you with the results in a moment.
Sensor Off:
m119
SENDING:M119
Reporting endstop status
x_min: open
y_min: open
z_min: TRIGGERED
filament: TRIGGERED
ok P15 B3
Sensor ON:
m119
SENDING:M119
Reporting endstop status
x_min: open
y_min: open
z_min: TRIGGERED
filament: TRIGGERED
ok P15 B3
Well, now, I’m a little confused about this because the results are exactly the same whether the sensor is on or off. 
Oh! I just re-read what you’re saying. Okay, I’ll try the test this way as you suggest. I think it’s working though.