EB-18 Scales of War

Hi Steven, we’re shifting our releases to the end of each month to better accommodate previews and play tests. Expect EB19 at the end of this month, the epic in October, and EB20 in November.

Those are the statues. We'll fix the text - I think there should be four of them. Thanks!

Just wait for EB-19. The nature of the Oracle begins to unfold...

Just wait , just wait … until part 19 (?) well clearly there isn’t much time left so one would hope so.
It’s a missed opportunity to not make the oracle an NPC instead of the players lugging around a juke box that occasionally gives obvious or minor advice that may only possibly effect an encounter in a minor way.
In my campaign early on there was an arcane confluence / explosion and the spirits / Essence of the oracle became fused with one of the PCs who is now sharing head space with the triune . She has been changing over time as her spirit melds with theirs based on the limited info I have on it.

To be clear, I am comparing them to the different idea presented in Exploring Eberron, which has siege staffs as long-ranged bombardment devices.

(Haven't read this adventure yet, playing it first.) The mechanics you cited are copied from the Salvage Base guide's T4-only upgrade, the Spell Staff. Since some lucky parties may be marching on the LoB with their own mobile salvage base fitted with such a Staff, I guess it makes sense to use the same rules.
Plus, Explorring Eberron isn't an AL resource (sadly), so there isn't necessarily coordination between that book and this campaign.

The transitions between adventures has been abrupt throughout the whole series, definitely one of the weak points of the campaign. One if the pitfalls of the AL format (?).

If you've only just started this campaign at EB-17, then you've unfortunately missed a great deal of the hooks and foreshadowing from all those previous adventures. The true threat posed by the Lord of Blades was first established when relevant lines of the Draconic Prophecy were uttered in EB-11, and the adventurers were subsequently leveraged to assist negotiations between nations in preparation for this assault. The information acquired in the last adventure was the last missing piece of the puzzle required before initiating this assault, for which preparations were well underway, as indicated by the news article uncovered as part of that investigation. And any adventurer that played through the earlier Dogs of War adventurers (EB-08 through EB-10) are probably itching for some real payback and thrilled to join the front lines.

Transitions might seem abrupt between the end of one adventure and the beginning of the next, but I'm choosing to embrace that as a feature of the Eberron flavor rather...See more than a fault of the AL format. The tone of Eberron has always been explicitly intentional about copying the cinematic flair of action/adventure films, and part of that flair means skipping over the boring parts and jumping more immediately from one event scene to the next. One moment, you're standing in Salvation, standing amidst the wreckage of an all-out battle for the town, pondering the whereabouts of the escaped mastermind as the screen fades to black. Next thing you know, the camera pans across the busy scene of Terminus Station, the caption "Sharn" displays across the background, and you see your adventuring party step off the lightning rail, already talking about the lead they've come here to follow, and maybe joking about individual character hijinks during the trip which occurred off-screen.

I have been keeping track of Oracle of War since adventure #1.

That the Lord of Blades is a major threat has been clear. Far murkier is the fact that the Five Nations have been assembling a coalition to take down the Lord of Blades; this has been squarely limited to one-off mentions aimed towards the DM rather than the players, and in small paragraphs in news articles.

The Five Nations uniting to forge a coalition army is a major event that is kept mostly "off-screen," and the players are quite likely to be unaware that it is happening. It is also probable, then, that the players will be blindsided by the abrupt appearance of a grand, unified coalition army of the Five Nations.

EB-11: While the PCs are meeting the Twelve, the Oracle delivers a prophecy that confirms the threat posed by the Lord of Blades.
EB-12: The Twelve send the PCs to Thrane as part of a peace mission to gain their help for the coming alliance.
EB-13: The PCs meet the Keeper of the Flame and present their case for alliance. If they impress her, they earn a legacy event pledging Thrane’s aid.
EB-17: King Boranel sends the PCs to New Cyre to locate the missing forge, saying that if they can locate it, he’ll pull Breland, Karrnath, and Aundair into the alliance.
EB-18: The alliance forms and marches into the Mournland.

The issue here, I think, is that the "build an international coalition against the Lord of Blades" segments really are limited to one-off mentions. It is not a spotlight subject. In particular, adventure #13 does not even mention the Lord of Blades in the adventure text; it simply assumes that the players are warning Jaela Daran about some much vaguer threat to Khorvaire.

Adventure #17's starting sequence is about the closest it gets to being spotlighted, but by that point, it is much too late. There is very little opportunity for a buildup from that point. The characters really are tossed from a small town murder investigation and directly into an already-assembled, gigantic coalition army by the next adventure.

If you go back to EB-12 / Part 1 / Mission Briefing, you'll see it specifies that the Twelve have sent notices to all nations calling for this unified front, the Thrane/Breland tensions are an impediment to that alliance, and that Jaela Daran specifically requested to meet the adventurers to help inform her decision on that alliance. That conversation with her in EB-13 should have occurred with both Jaela and players aware of this desired goal. Furthermore, the EB-13 adventure specifically guides that conversation to explain the Oracle's prophecies, of which the most recent definitely concerns the Lord of Blades. These details aren't merely "one-off mentions," they're key aspects setting the background and motivation for these arcs of the campaign. As such, in my experience reading through these adventures, I found the foreshadowing and buildup you requested to be more than adequate, and I've been very pleased with the results.

If you accidentally missed those details and ended up playing...See more through EB-12 and EB-13 very differently, discussing "some much vaguer threat to Khorvaire" instead, then I can see how the news of this alliance in EB-17 might seem more sudden, and how it could have changed your experience from mine. I have sympathy for the frustration that probably causes. Perhaps there are opportunities to make that direction a little more clear if future revisions are applied to these adventures (for instance, I agree this background context should probably be more specific somewhere in the Overview section of EB-13). But given the plan for this alliance was still explicitly declared in the text of EB-12 and the adventurers should have negotiated with 3 out of 5 of those nation's leaders, I think it's inaccurate to suggest the foreshadowing and buildup of this event was minimized in the campaign.

I’ve been playing since the very beginning. The transitions have been abrupt, not a huge deal but it becomes more apparent and difficult to manage as it rolls along.
Both my players and I absolutely loved the series early on, and thought it was one of the more original, creative things we’ve played in some time .
I think part of frustration is serialized format, as a DM I’m simply not able to read whole thing before play.
I hope the final adventures stick the landing, and that they are not delayed…

Personally I can't see what you're saying as anything more than a tiny nitpick that's totally overshadowed by the scope and quality of this campaign. I've played all the modules prior to this one and will have the privilege (if all goes as planned) of running them over the next couple years with the benefits having played first; to our party, the coalition building has been a clear B Plot to our A Plot for a long time now, and it was used as an elegant narrative device to send us places we otherwise wouldn't have had any business in (like Aundair and Thrane). Negotiating this sort of thing doesn't seem like an appealing use of time compared to the pulp adventure we get, as Jeremy said.

Just as we can't read the whole 1-20 campaign all at once, the company can't feasibly hand it all to one author or tell the DMs precisely what's coming.
My two cents.