From the logs i can see that this isn't probably related to devfee-user pool switching, because after the devfee finished, you got jobs and accepted results from your pool, so the switchback was successful.
[2018-06-03 03:09:20] switch_pool: Disconnected from devfee pool, now mining for user
[2018-06-03 03:10:26] hashrate: GPU0: 964 H/S [BUS:5]
[2018-06-03 03:10:26] hashrate: GPU1: 1013 H/S [BUS:6]
[2018-06-03 03:10:26] hashrate: GPU2: 1017 H/S [BUS:2]
[2018-06-03 03:10:26] hashrate: GPU3: 964 H/S [BUS:4]
[2018-06-03 03:10:26] hashrate: GPU4: 952 H/S [BUS:1]
[2018-06-03 03:10:26] hashrate: Total: 4910 H/S
[2018-06-03 03:10:59] json_receive: {"jsonrpc":"2.0","method":"job","params":{"blob":"010193e4ccd805375fd1190a992e2b57929b47ae079a998a31bc7e1c11111a5a43e932b87519c20 0000000e510944a66dda1a13a8c31101b4cd678c25c109320e76a7936b82ff0fc10938201","job_id":"436392239714041","target":"d96f0000"}}
[2018-06-03 03:10:59] pool_have_job: Pool sent a new job (ID: 436392239714041)
[2018-06-03 03:11:09] miner_result: Sending user result to pool
[2018-06-03 03:11:09] json_send: {"method":"submit","params":{"id":"316536043444648","job_id":"436392239714041","nonce":"964033b3","result":"23e46068b4c15131a3d638b862f4988b4f810f82aa7b46a2d4cf0a91360b0000"},"id":1}
[2018-06-03 03:11:09] json_receive: {"id":1,"jsonrpc":"2.0","error":null,"result":{"status":"OK"}}
[2018-06-03 03:11:09] miner_result: Pool accepted result 0x00000B36
also there are new jobs/accepted shares after this before the fun begins :
[2018-06-03 03:31:29] json_receive: {"id":1,"jsonrpc":"2.0","error":{"code":-1,"message":"Unauthenticated"}}
[2018-06-03 03:31:29] miner_result: You are not authenticated to the pool
[2018-06-03 03:31:29] miner_result: Pool rejected result 0x00003690 (unauthenticated)
[2018-06-03 03:31:29] miner_result: Network error
[2018-06-03 03:31:29] miner_result: Network error
The 0 hashing speed in this case is normal, because the GPU's are not working on any job.
This looks like some kind of pool problem to me.
it's happens on different pools and different algos