I'm not an expert, but being an English teacher, I'd say I have some experience with matching signatures to handwritten text. These appear to be written by the same person, Robert Costello.
Here's another example.
1. Pre-tape of memory scence picked up cross talk, had to break for lunch, and do it later. Much time lost.
2. Taped Dress-NO time to tape "AIR".
This was regarding episode 584. Taken to the hidden room in the mausoleum, Maggie (Kathryn_Leigh_Scott) begins to remember her awful experiences of the past year. Barnabas (Jonathan_Frid) decides the only way to save Victoria is to kill Adam, aired September 19, 1968, taped September 12th.
http://www.starpulse.com/Movies/Dark_Shadows:_Episode_584-V247965/Summary/