Chirpstack Gateway Bridge and Multiple backends

I have been using the UDP Packet Forwarder on the Gateways sending to the Chirpstack Gateway Bridge.
But want to start moving to Basics Station.
My question is whether an instance of the Gateway Bridge can only support one backend or whether you can enable 2 or more?
The config line shows 1 selection:

# Backend type.
# Valid options are:
#   * semtech_udp
#   * concentratord
#   * basic_station

So from this, am I correct in that you can choose just one?
If so , how else can I achieve the desired result (without installing the bridge on each Gateway - some of the gateways don’t have the resources needed for this)

I think you will have to deploy different gw-bridge endpoints. If you have a load-balancer in front or you are proficient writing iptables rules, you could host both services under the same IP. They use different Ports/Protocols so it should be possible to redirect according to that to the proper backend (UDP or BasicStation) - havent done a config like that myself but maybe this helps: