Removing boxing from around a beam. How big a job is it?

[pastabest]

Just that really. I've googled extensively but can't seem to find an answer.

Very old house. At some point in the past most of the beams upstairs have been boxed in and papered over with wood chip paper.

Is the whole ceiling (chip board) going to come down if I try and remove the boxes? Is that actually a blessing in disguise if they do, is it a big job to put a new ceiling in or is it a case of screwing some new plaster board in place.

It is a grade 2 listed building but as far as I'm aware the chip board isn't listed...

Example of one of the rooms in the attached picture.

I'd drill a few investigative holes first to see what's under there - might be best left alone.

We had some mysterious boxing in our old kitchen - finally removed it to find there was a beam "holding up" the rotten upstairs floor joists... which would have been fine if it was actually attached to anything It was under the bath - the builder was not quite sure how the bath hadn't fallen into the kitchen.

Cheers. I'm fairly certain it's just been done as a style choice rather than to hide anything. Either way, I hate the boxes and the woodchip so I want them gone. Just wondering if it is a £500 job or a £5000 job!