RX, TX, timestamp and SoapySDR

Thanks,

So for TX-only app, do I have to use “real” timestamps or can I always use 0? Are those buffers simply put in a queue and sent as fast as possible, no matter what their timestamp is?

As for RX+TX app, is there an order to set things up? For example should I first setup the RX part, start its stream, and only then setup and start the TX stream, using a big enough timestamp to make sure I’m not late?