i haven't done that, yet but once I do I will update you.
Yesterday morning I saw that the bridge was emitting blue light (it was blinking constantly). I didn't had time to look so went out. When I came back home the bridge was not emitting anything (is there any indication that the bridge is on?). I looked in the app and Bridge Diagnostic menu was there, and clicking it gave me all okay. So I didn't bother restarting the bridge, assuming that all is good.
This morning bridge was not emitting any light, and bridge diagnostics was all good, I kept the bluetooth off on my phone and over wifi I was able to unlock/lock my bolt (albeit with some errors like after I issued the command i got the error something like unable to process your request try again, even though bolt unlocked/locked).
After around 30 mins later the app couldn't find my lock, and the bridge diagnostics was gone. I turned bluetooth on and was able to unlock/lock my bolt but I think my bridge was just offline.
I didn't had time to do what you suggested on restarting, but when I get home I will have a look into it.