It's quite early to be hearing these guys! Lots of radio reports, radio checks...and whistling into the mic makes me believe this is another freebander net, similar to what's heard on 6900 kHz and other similar frequencies.
1245 UTC - hearing what sounds like a YL talking to the (stronger, possible "net control" or "primary" frequency), sounds like a personal conversation
1246 UTC - YL (weaker station) seems to have faded down into the noise