Once you're able to use time as an information, they can send a message with a character limit. For every letter they need to wait:

Remaining Message Length^Alphabet Size*Index of Letter*time interval

So, if future people want to sent the message hello and our time unit is 1s, and the max message length is 5, they need to send the bit to exactly 26^4*7+26^3*4+26^2*11+26^1*11+26^0*14 = 3276872 seconds or 54614,5333min or 910,242222h or ~38 days after the start time.

We can choose smaller time intervals, but with a long enough message, we'll eventually reach the year 3000 again. Alternatively, we can move the start time into the past, at the expense of quite a few possible messages.

This is the same problem as trying to map an n-dimensional array to a one dimensional array

that's more than one bit, though, which is part of the question's constraints. In practice that means [No response] would be the same as indicating 0 or even 1 and they cannot convey additional information by controlling for time of receipt, likely because they can't control time of receipt

if no response, we'll assume ur dead

And there was no response, for Ur - the city - died millennia ago. If only Skippy had stayed in school.

The options are 'yes' and 'double yes'.

In the year 3000, comedy has reverted back to the year 2000. What is this, a year for ants??

Clop clop

And that's how we found Trump's Lemmy account.

Not much has changed, but we live under water

Thank you for saving me the effort of putting that and not knowing how well it would go down. Do Americans know of Busted?

Year 3000, every single human is born from a biological reactor, they're genetically modified to be subservient and strong and infertile. Everyone on earth serves and praises the few remaining masterminds who locked their brains in jars, kept alive by nutrient tubes

No. Here, I saved you your question, you get to ask something else.

The annoying thing is we won't be able to know if we can trust the answer. I f you'd ask now there's also people who'd say yes.

'!' and the first few letters of the community name should give you a list to choose from. Comes out like !asklemmy@lemmy.world.

No response.

I think we already know the answer to that one.

Put it in a box with a cat, a vial of poison and a decay timer that releases the poison. Obviously.

Edit: Just what is this downvote supposed to mean? Someone get me a box.

Eithet 0 or 0 because we've already been told they exist

They’re just backup copies hosted in the Galactic Museum. There’s no way a species that stupid would survive long enough to invent FTL travel. Just surviving the nuclear era was borderline miraculous.