Offline URU using Drizzle is a nifty bundle of hacks. Same thing goes with an alcugs-based shard like Deep Island. That's the reason why they are standing on the wrong side of legality, for our own (guilty) pleasure though...
Gehn Shard on the other hand is a MOUL-based shard. The extent of the hacks enabling to run that shard is less extensive. I don't know all the intricacies of the deal but I'm pretty sure they cannot alter any of the assets of the game. In which assets, we find things like panic zones, collisions, sound regions, game mechanics, etc. During events, they can alter them, I've been in such events where they would mess up a given age but it's always a temporary thing, (the bots in MOULa shard do that on a permanent basis, it doesn't change the assets on a permanent basis though).
And we don't have to look very far to find "official hacks" made by Cyan themselves... MOULa shard has one of the most popular hack in the community making every other shard looks cheap in comparison... they have enabled all the sparklies at once! In this deal, we gain in speed to collect all sparklies but everyone is questioning the other shards why they have a policy of: "one sparkly by month". The quickest answer to that is, everyone is doing it right except MOULa with their hack
So altering journey door time would might be consider like altering an asset. For a MOUL-shard like TOC MOUL, the line is really thin. They get away with their "City of Dimension" because they keep a live version of City of Ae'gura. They would drop it, it would be illegal. They created an exact copy of Ae'gura and then altered it on permanent basis.