The Senders Deliverability Dept. tier runs on a quarterly cycle. The first quarter is the Q1 intensive — the heaviest engagement period — and subsequent quarters continue at the ongoing rate. There's no minimum commitment past Q1, no "12-week program," no retainer lock-in. You can stop at the end of any quarter.

But "how long does it last" is really asking: at what point does the problem stop needing engineering attention? That depends on what's wrong and how complex your operation is.

Real Examples of Different Timelines

A company on the Deliverability Dept. tier comes in saying their authentication isn't working. The Deliverability Engineer runs the diagnostic, finds a broken DKIM record, walks them through the fix, validates it's working. The Q1 intensive continues — there's still the audit, the monitoring setup, the backup domain work — but the immediate problem resolved in week 1. After Q1, the company decides they don't need ongoing engineering attention and steps down to the Business tier. Total time on the Deliverability Dept. tier: one quarter.

A different company comes in saying their mail started going to spam three weeks ago. The engineer diagnoses a reputation problem caused by a too-aggressive volume ramp. The Q1 intensive becomes a reputation recovery program: reduce volume, clean lists, adjust cadence, monitor reputation recovery. Recovery takes most of the quarter. They continue at the ongoing rate into Q2 to make sure reputation stays stable as they scale back up. Total: 2 quarters before they're confident enough to move down.

A third company is running cold outreach, transactional email, and marketing email from overlapping infrastructure, and everything is degrading. Q1 implements proper segmentation, fixes multiple reputation streams, and establishes monitoring. After Q1, the complexity of running three streams means they want a Deliverability Engineer permanently in their corner — they continue indefinitely at the ongoing rate.

A fourth company is running high-volume cold outreach and wants to scale safely. Q1 sets up the warming and infrastructure. Ongoing quarters are continued monitoring as they ramp volume from 10k to 100k emails per day. They continue for two years and counting.

Every one of these timelines is different because every problem is different.

The Diagnostic Always Comes First

Every engagement starts with the diagnostic. This answers the core question: what's your problem, and how much engineering work does solving it actually require?

The diagnostic takes 1–2 hours and is part of the Q1 intensive. At the end of it, you know:

• What's actually causing your deliverability problem
• Whether it's a small fix or a systemic issue
• What the rest of Q1 will be spent on
• Whether you'll likely want to continue past Q1 or step down to a lighter posture

You never sign up for an engagement length you don't understand.

Factors That Affect Duration

Several things determine how long you'll want the Deliverability Dept. tier:

Severity and complexity of the problem. A simple reputation spike might resolve once you fix the underlying cause and reputation recovers naturally. A deep systemic issue with multiple problems interacting (reputation damage compounded by authentication gaps compounded by list quality problems) takes longer.

Your execution speed. The engineer guides and validates. You execute on systems you own. If you can implement DNS changes quickly, update your ESP configuration immediately, and adjust sending behavior right away, work completes faster. If you need time to coordinate across teams, get approvals, or schedule implementation, it stretches.

Complexity of your infrastructure. A single-stream operation sending from one IP to one domain is fast to assess and fix. A company managing cold outreach from three domains, transactional email from two domains, marketing campaigns from another domain, and lifecycle email scattered across multiple infrastructures takes systematic work.

Regulatory or compliance requirements. Some verticals have stricter email standards (finance with DKIM enforcement, healthcare with patient privacy implications, gambling with strict fraud requirements). This extends the rigor required for implementation.

Your ongoing needs. Some companies solve their immediate problem and move on. They step down to the Business tier or off Senders entirely. Others realize they're running email operations at a scale where having an engineer permanently in their corner is worth the rate.

Quarterly Billing, Quarterly Exits

The billing cadence is quarterly. So is the exit cadence. You can decide at the end of each quarter whether to continue. There's no annual contract, no retainer minimum past Q1, and no automatic renewal that locks you in.

This matters because it means the engagement scales to your actual need. Solve the problem, exit. Realize you need ongoing engineering attention, continue. Hit a new crisis later, come back.

What Happens After You Exit

After leaving the Deliverability Dept. tier, you have a few options:

• Step down to the Business tier (keep the Managed Email Infrastructure layer and the self-serve monitoring suite, drop the dedicated engineer)
• Step further down to the off-menu Deliverability & Monitoring Suite ($250/month for up to 5 domains, +$50/month per additional domain — no engineer, no Slack, but the monitoring stays running)
• Move off Senders entirely if you've built sufficient internal capability
• Come back later if a new problem emerges — the Deliverability Engineer who knows your system is available again

Most companies pick one of the first two. Some exit completely. Some stay indefinitely. The structure supports all of those without penalty.

The Real Measure: Start With the Diagnostic

The best way to understand whether the Deliverability Dept. tier is the right level for your situation is to start with the diagnostic. You get clarity on what you actually need. From there, the scope of the Q1 intensive becomes obvious, and you make an informed decision about whether to continue past Q1.

You're not signing up for something unknown. You get the diagnosis first, then you decide quarter by quarter.