It doesn't matter if the grief happened yesterday or two months ago-- it's the fact that if the grief is brought to the attention of a moderator+ that you can still be caught. I was over in that general area responding to someone's cry of need and I found a building built by bigmama68. I had found around 32 blocks of damage done to this building by you, and you weren't the only one to inflict damage to that. If this was in error, please tell me now.
If I remember correctly, the ban was only set for 3 days.
One other thing to add: If he wanted the building taken down, he would've done that himself or at least have had some of the block history with him breaking the blocks himself. Since there was NONE of that, there is NO way this was any sort of allowed demolition, as far as I am concerned.