My question may be very basic. I have a single channel Dragino LoRa phy layer to SPI/I2C/IP/USB/etc. “< delete as appropriate >” bridging device.
There FTFY! 
Irrespective of end node duty cycle etc. (Clearly a fail as well called out above) IMHO such GW’s should not be encouraged on the network as they confuse and cause problems for other users in range, degrade network performance/cause ‘failures’, and can cost real money to diagnose and fix/avoid/mitigate presence of. There is simply no excuse to use single (or even dual) channel devices when there are now so many ‘micro’ GWs available at relatively low cost that are LoRaWAN compliant (single/dual channel devices NC by definition) inc the TTN/TTI TTIG, and micro GW’s from others such as Dragino (if you want to stay with them) e.g. LPS8 LPS8 Indoor LoRaWAN Gateway , RAK RAK7258 - micro indoor gateway, etc. and many more coming every month e.g. posted to forum just today Product Announcements - #194 by monicalaw07
/Rant off 