The four year degree is treated as the safe option and the thing you do if you are unsure. It is a large commitment and it deserves to be chosen rather than defaulted into.
The offer refused in month two is often better than the outcome reached in month fourteen, once you count what the intervening year actually took out of you.
A dwelling limit set when the policy was written and never revisited is the most common form of under-insurance, and the clause that enforces it is easy to miss.