I'm no expert but a post on Facebook is not an email or a telephone call - telephones calls and emails are specifically addressed to an individual and can be traced back to the sender/caller. I would certainly argue that;
a) someone else posted the information (how and why you have no idea but there are other people in your house that could have accessed the computer no doubt)
b) Someone must have specifically looked at your Facebook to find the information, so why did they do that and who was it (i.e. somebody possibly has it in for you and is looking to harrass you)
c) In what way does it bring RM into disrepute if RM isn't mentioned, it could have been directed at the US Postal Service or Deutche Post, who can tell.
As mentioned above, they need to prove that you wrote it, that it was directed at RM and that it does bring them into disrepute.
Then to use your own words a post on Facebook is not an email or a telephone call - no arguments there but it is however a form of electronic communication.
"Today’s workplace has become heartless and soulless. Employees are seen as units of labour, automatons, functionaries, objects for achieving designated tasks, and as costs to be minimised."
This isn't new We had a lot of this in 2007,also we've had sackings,(reinstated thank god) threats,suspensions for posting on RMC,Facebook and youtube.
I Wrote-During Covid-Which is still relevant now
It's good to get these types of threads, the ridiculous my manager said bollox, so we can reassure ourselves that while the world is falling apart, Royal Mail managers are still being the low-life C***S they have always been. My BFF Clash The daily grind of having to argue your case with an intellectual pigmy of a line manager is physically and emotionally draining.