Your sarcasm is all well and good, but even the OP already suspects in the original thread that something is coming down on him that he cannot avert, but at best can only buy some time; direct quote, all from the original thread:
"There was an order from the building authority last year to remove this 'enclosure'. In a personal conversation, I was able to obtain a 'grace period' until summer 2016." [...]
"Last week I received a letter from the building authority saying that I still wouldn’t be finished with my construction and that the building permit was no longer valid." [...]
"Now I need another 3 - 4 months."
If you have some practical professional experience, it’s not a big step from there to follow the relevant post by , who expressed his suspicion quite clearly. At least the OP’s behavior fits with that.
What the OP received is therefore no invitation to a "coffee gathering under the enclosure" that one irrevocably rejects, but rather a friendly scheduling for an on-site appointment - if the appointment does not take place, it is solely at the discretion of the caseworker when the next letter with the same content, supplemented by the respective criteria that you do not want to see fulfilled here, will be sent out.
Assuming you are actually as well informed as you claim, you should know that this only requires a few keystrokes.
Dirk Grafe