Another random part of the Equestrian official apparatus - and why Spike was away in Look Before You Sleep

The Royal Messenger Service has been part of various arrangements over the centuries. Once it and the Office of Public Proclamations - which now also handles most press liason work for the Crown and the government - were two wings of the same pegasus, so to speak. Later, after their division and at a time when they were highly-developed and royal funds low, Princess Celestia allowed their services to be rented - a decision they would have accepted from no-one else (and even on her word caused some dissension) but which ended up forming the foundation of the Equestrian Mail Service. And while the Messenger Service would never return to it's former size and prestige after breaking away from said Mail when it passed out of direct Royal control, it was a choice they saw as necessary to preserve their focus on their original mission - to carry the missives of the Princess (or her appointed agents) to any who needed to receive them, and bring back the replies.

Of course, while Princess Celestia had always deeply respected the Messenger Service, she had also always had her own ways to communicate more discreetly with certain parties if need be - she was just polite enough to never let them catch wind of this. And if any in the RMS got the idea she was, they were also polite enough to keep it to themselves. Perhaps it was this polite understanding which meant that the Princess teaching a young dragon how to convey letters directly to her by magic passed beneath RMS notice... or perhaps they genuinely didn't know. And as for how they became unable to ignore it... well, it's unclear, though some say the newly-returned Princess Luna, who knew nothing of such subtleties, had something to do with it.

Whatever the case, the knowledge of such instant correspondence stirred up simmering worries in the old organisation, long-shrunken from it's glory days. Unlike the Office of Public Proclamations, the RMS had been slow to adapt to the rise of railroads and telegraphs, and recent decades had also seen most less secure government missives switched to the Equestrian Mail Service. While "Celestia's Carrier Pigeons", as they were called, still saw quite a bit of work, particularly from Her Majesty herself, there was a fair bit of worry (largely not spoken out loud) that they were going to be replaced by scroll-burping dragons, enchanted journals or (in one junior member's rather imaginative rant) "a device which allows Her Majesty to send her voice along the telegraph lines in an instant - or perhaps even through the air itself!"

Well, suffice it to say, it took Princess Celestia a bit of work to calm the whole matter down and reiterate her commitment to the RMS no matter how magic or technology evolved (while implying that it would do them well to focus on working with said evolution rather than focusing solely on their historical paradigm of running, flying or teleporting agents). And since this whole business started with Spike (sort of), part of the reconciliation involved him being brought in to undergo a special course and initiation as an honorary member of the Service. (The young dragon's pleasant nature certainly helped with the reharmonisation, with even some of the more paranoid members claiming he was impossible not to like.) The whole thing took a couple of days overall, including him accompanying Messengers on a mission, and was the longest he'd been apart from "his Twilight" for quite a while. He was quite excited by the whole thing... though he did spend some time wondering after the fact if it was worth missing Rarity spending the night.