From next year, national post will be handled by a different company than currently does the job.

From next year there will still be one private company claiming to offer this service, yes, but they are under no obligation to keep doing so, and if the market is already so unprofitable that the national postal operator immediately exited it once freed from the obligation of remaining in it, it is questionable how long a private company will remain.

One particular concern I have is whether that company will be connected to the Universal Postal Union; if they aren't, sending letters to and from foreign countries will suddenly be a minefield. I don't know and have been trying to find out.