What are the things to be noted or considered if a software which was initially treated as DAL C and later wanted to be considered as DAL A?
1$\begingroup$ Read DO-178C and look for the different requirements between level A and C. $\endgroup$– Daniel KJun 24, 2018 at 16:27
3$\begingroup$ This question is understood by software developers familiar with certification requirements. $\endgroup$– PilotheadJun 26, 2018 at 12:33
The main difference in effort is in the amount of verification required.
Design Assurance Level (DAL) C only requires statement coverage whereas DAL A requires MC/DC coverage.
Some of the DO-178C objectives have to be meet with independence where they didn't need to be previously, and some life cycle data goes from CC2 to CC1.
I would suggest looking at the objective tables A1-A10 in DO-178C