Do what you can when you can.
Took me 4 yrs to get an AAS while working full time.
Started on BS at age 27 - didn't finish till age 35. Worked full time most of those 8 yrs.
Did finish the MS in 1 yr.
Took me another 10 yrs to go the rest of the way.
Holy cow.....that's a long time. But at least you made the commitment and finished it all. That in itself is an achievement! Gives that diploma hanging in the office that much more meaning.
It also shows he has real world experance instead of just book knowledge. One more reason to look at his program.
If you have that kind of determination to stick to a goal that is great. I just know that too many of us get complacent and comfortable half way through and never finish.