When using the signal planner, it will upgrade signals and add new ones, but it doesn't seem to remove redundant signals anymore. This sometimes results in signals being added in the right places and then an adjustment is made to the rails and more signals are added in the new right places.

Can you give an example with a picture or blueprint?

I have made it so it respects old signals if there is no harm in them being there. Mostly so that signals don't keep changing positions when laying long tracks.

They will only be removed if they are part of an exit.
(Chain signals are a bit more tricky and are even less likely to removed)

If needed I can revert the old behaviour when using the tool and the new when laying tracks.

Thanks for the response LeonSkills. I was surprised at the behavior change, and how differently it behaves. Now that I've toyed with it a bit, it makes a lot of sense. I had a bonkers set of signals and once I just ripped out the existing garbage mess, your mod did exactly what I needed. I really like the new behavior. Thanks for the great mod, and all the effort.

FYI I think the biggest mental change from 1.1 to 1.2 was how the new behavior seems to work at the rail-block level; not by applying signals to the selected rail entities, but by apply signals to the select rail blocks. It's useful that a single click without even dragging can signal a block.