One councillor (a Cons one) was phoning up locals in the village, the evening before the committee hearing, asking them to come along and object.
Sounds a bit bizarre. Whilst "public speaking rights on planning applications" is in general a Good Thing(TM), there do need to be some rules. On my council the rule is that if you've put in a written objection in time then you may speak against, provided that you give notice, again in time, of your intention to speak. (That's notice to officers, of course, not councillors.) "The night before" is far too late for both.
There is, by the way, nothing wrong with a councillor campaigning either for or against a planning application, provided
either that they're not a member of the committee
or that they declare at the meeting that they're taking sides and withdraw from the room whilst the application is discussed and voted on. The rules about how much they're allowed to lobby their mates on the committee in private before the meeting are a little unclear, but
it's absolutely clear that it's completely illegal for their mates to make their minds up before the meeting, or for there to be a party whip.
When either applicants or objectors ask me for my support I point out to them that if I were to offer them my support they wouldn't get my vote, as by law I'd have to leave the room whilst the application they're interested in is discussed. At this point most people decide that they don't after all want me to declare for their side in advance and are happy just to make sure that I understand their point of view.