Consent form at the first showing or at the offer, does the timing change what you're agreeing to?

Timing matters to you even if it doesn't move the paperwork. I've signed one early and one at the offer, and the early one is the one I regret, because by the time it applied I'd stopped thinking about it. When she said she couldn't advise me on price I was surprised, and I shouldn't have been. It was in a document I'd signed eleven weeks earlier without reading past the second paragraph.

There are two separate documents doing separate work here and the agents may each be describing one of them.

Most states require some form of agency disclosure early, often at first substantive contact, which tells you who represents whom. That one is informational and signing it doesn't consent to anything. Dual agency consent is a different instrument. It's the one where you agree that the agent or brokerage may represent both sides and accept the limits that come with it, typically that the agent stops advising on price and stops disclosing either party's motivation.

When consent has to be obtained, and whether a blanket consent signed in advance is valid at all, is set by state law and varies. Some states require the consent to be property specific and obtained before the agent begins representing both parties in that transaction. Others accept an advance consent in the buyer representation agreement. Your brokerage may also have its own policy stricter than the statute. Ask the broker which state rule applies and get the answer in writing, and if the validity of an advance consent is what your deal turns on, that's a question for a real estate attorney in your state.

Practically, the form does the same thing whenever you sign it. The difference is your own attention. A consent signed against a known property, a known seller, and a known price gives you a reason to ask what the agent will stop doing. Signed in the abstract at a first showing, it usually gets no reading at all.

Asking whether designated agency is available is a reasonable third option, and whether the office can offer it depends on state rules and on having another licensee to assign.

rigging, one more thing to watch. The blanket version is often buried inside the buyer representation agreement rather than sitting on its own page, so people who think they never signed a consent have. Search your own copy for the word dual before you assume you're clean.