NOTE: this post was relocated to a different thread than it was actually posted in. It does not entirely make sense here, in the way that it did in its original context of the preceding post it was directly responding to:
If you manage to get a downlink sent in reply through to the node, then you know that the overall (vs gateway) time listed is consistent across nodes within around half a second.
There could be more of a difference (ie, due to backhaul network latency) but if there were, then downlinks wouldn’t work. Even typically RX2 downlinks, as the network servers tend to hold packets until shortly before their send time out of an assumption that gateways are still running original packet forwarders unable to accept a queue of packets to send in the future.