Hello, I face the same issue of HTTP 503 but want to have queue instead of just leaving this problem as it is.
I have one Bridge with 2 devices: the nuki smart lock and the nuki opener
My use case is to use the opener to open my front door first and secondly use the smart lock to open my home door:
http://192.168.1.3:8282/lockAction?nukiId=0E5AE929&action=3&token=*****
http://192.168.1.3:8282/lockAction?deviceType=2&nukiId=2A2F2AEA&token=****&action=3
The problem is that the opener stays in a busy state and no other command can be sent within about 20 seconds. I always get the HTTP 503 code. So what happens:
We live in ground floor so we open the front door and waiting 20 seconds in front of our home door to let it open.
We programed a remote control to send both commands via http.
When we go to the garden we are not far away for automatically open any of both devices. so we need a better way to open both doors without using our smartphones (unlock, open app, tap on opener, waiting, tap on door).
So a queue of requested commands would be great.