how can you use が on ある in 没までは まだあるが 出発するつもりか？

Question

I saw this sentence in an episode of attack on titan a person is surprised that his captors seem to be having a frantic conversation about moving him and leaving from where they are located earlier than expected this is because his captors just noticed that "law enforcement" is catching up with them the captor doesn't know this and is therefore surprised

没までは まだあるが 
> 出発するつもりか？

The translations were as follows (each from a different sub)

1. They still plan on clearing out before sundown or not?

2. Are they planning to leave before the sun sets?

3. Do they have some reason they need to leave early?

I don't understand why there is a が on the ある. Isn't ある a verb? Is this a normal construction or is there something else I'm missing?

Answer 1

I suppose there's a typo: 日没まで.

The construction omits the subject 日没まではまだ時間があるが. The last が is a conjunction meaning but, not the subject particle. Literally the phrase means There is still some time till sunset, but are you gonna leave/set out? (The speaker is implicitly assuming they should set out after dark).

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The omission is common for time or distance.

• 東京につくまでまだだいぶある (e.g. on trains) = it will take a while before we arrive in Tokyo (sounds more like time)
• 東京まではだいぶある (e.g. on road) = there is a long way to go before we arrive in Tokyo (sounds more like distance)
• 晩御飯までにはまだすこしあるからなにか食べよう = Let's eat something because there is still some time before dinner.

As seen in these, I think it is more common to use them with some quantification (すこし/だいぶ), but まだある also works in most cases.