and replaced with teams from D5 with the best records.
That is not accurate. The teams that win the regular season title in a division are promoted over second place teams
from the other division with better records. If you do some checking, you will see that division champs with worse records than the second place team in the other division get promoted, while the second place team with a better record stays put. So unless you win the regular season or playoffs, you are doomed to stay in D V, even if you have the second best record in your League.