I seem to hear mixed opinions on this. From a personal perspective, my one experience of warranty returns with Bitmain was excellent. I bought a new S17+, which failed after a few hours of use. I returned to an address in the Netherlands (as advised by Bitmain) and literally the next day they shipped out a brand new miner from China. I had a replacement the same week I shipped the faulty unit (which I consider to be excellent service).
I believe it has to do with the pandemic, perhaps your experience is not recent? anyway, it's a risk either way.
As for how much is outstanding, currently 88 days.
This is pure speculation on my side, but I believe 88 days from now will be the post-mania phase, sending the gear later would IMO be a lot better, also here is a tip for you, try to push them more to accept a hashboard-only shipment, generally, it's a NO, but Bitmain is rather flexible.