In the 1.12 update the default lifetime for the Stone Oven fireplace was changed to 14400 (4 hours) which is actually half of what the regular fireplaces and indoor fireplaces have! This can surely not be intended?

Previously it was a week (604800) making it a useful base item that would get refreshed by the flagpole. Since the oven requires a significant number of large stones to build, there is no problem with huge numbers of them being built and littering the map, so it should be safe to change the lifetime back to 604800 without any noticeable effects on server performance.