I took it to be a shift over to a new server platform/structure.
The various network tests that were being done indicated evaluations for some purpose or another. Then we suddenly have an outage where posting is disabled but "read only" is fine. That suggests they were performing an overhaul of how posting works and may have even been using a different network topography.
This is, also, just ahead of "big habbenings" that have the potential for a net shutdown.
Tinyboard is a very simple and flexible platform that is a sort of CB for the internet. It would not be surprising if there were plans in place to keep tinyboard platforms up and hosted in the face of larger network outages or DNS freezes.
I don't think it was an attack. I think we are seeing a rerouting of infrastructure in preparation for something big.
There again - I could be wrong. I have a mind for the sensational in the face of the mundane.