Tor client could not re-connect to a bridge which removed its obfs4 feature

I removed from a bridge (hashed fp: 662D4E4DE2C883625C543DFA3C4EE466899E6C85) the obfs4 feature and restarted the bridge. When I restarted now the Tor client configured as:

UpdateBridgesFromAuthority 1
UseBridges 1
#ClientTransportPlugin obfs4 exec /usr/bin/obfs4proxy
Bridge <snip>:<snip> <snip>

I got

Aug 15 17:39:23.000 [notice] Bootstrapped 0% (starting): Starting
Aug 15 17:39:23.000 [notice] Starting with guard context "bridges"
Aug 15 17:39:23.000 [notice] Delaying directory fetches: No running bridges

and the Tor client did not connect to the bridge. I stopped the Tor client, changed this line

UpdateBridgesFromAuthority 0

and now the Tor client could after a restart connect to the bridge. After that I could revert that change and now every restart of the Tor client works flawlessly.

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