18 Tx in a couple of hours is very good news! Was just browsing Cryptico's tests when you posted this, maybe the increased volume can explain the '' blocks before his two tests, see for yourself below.

Tree levels deep after two really complex blocks & 241 possible sources, things get really complicated & just one of that 241 leads to stuff like this (and if i remember correctly prev versions had  around 7 levels)
Let me zoom in a little for you ...
btw: the blue box is one of those 241 options as possible source of a non amount related input for his test.

Maybe this is the result of multiple anon transactions in the same blocks