An update to a level that alters its difficulty will cause all existing records for the level to be removed if and only if the level is harder enough to be raised on the list. All records will be maintained if the level maintains a similar difficulty or is nerfed to an easier state (e.g. WOW).
Any update to a level intended to change its difficulty in any way will invalidate all previous versions for future records on the list. Previous versions for levels that receive smaller updates, such as those that fix bugs in the gameplay, will still be acceptable for list records. The only exception to this is the case of Type II skips getting patched.
It should be noted that this guideline does not necessarily apply for the current hardest demon, because it cannot be raised any higher. Updates that increase the difficulty of the demon at #1 will be handled on a case-by-case basis in regard to keeping or removing existing records.
Many updates remove skips that had been accepted for records on the original version. Players should note that, per our guidelines for skips, existing records will never be affected after a level update that fixes one or more skips.
The only other change that may take place is for a fixed Type II skip, in which future records that use it will no longer be accepted.
Along with patched skips, a level may be updated to include a strong LDM or "Ultra" LDM that would not normally be accepted.
Records that were rejected for a strong LDM before such an update will be re-considered for addition to the list in accordance to the new LDM on the rated level.