New tiers can be added. What you can do to existing ones is really limited.
This does seem like w case where anither version of that tier at a higher price is a good idea. You can call it "Station Arcitecht mk II" or some such. Drinking Quest did that six times with its "get a compliment and insult card" tier, each being more expensive than the last.
I'd definitely add another one at $325 or some such. Early backers get a deal, but I'd the demand is there for such a high priced item, give the market what it wants. The biggest concern is Blue not being able to handle so many of them, so the next tier of it may need a later date to indicate the time requirement.