Vtyjkyuk

I built the v10 docker image and launched it exposing the HTTP port for core.

docker build -f Dockerfile.testing -t stellar:v10 .
docker run --rm -it -p "5432:5432" -p "8000:8000" -p "11626:11626" 
 --name stellar stellar:v10 --standalone

At launch, the protocol version is 0.

I then attempted to update the protocol.

curl "http://localhost:11626/upgrades?mode=set&protocolversion=10&upgradetime=2018-08-18T00:00:00Z"

The upgrades endpoint now reports v10.

curl http://localhost:11626/upgrades?mode=get

 "time": 1534550400,
 "version": 
 "has": true,
 "val": 10
 ,
 "fee": 
 "has": false
 ,
 "maxtxsize": 
 "has": false
 ,
 "reserve": 
 "has": false
 

But the most recent ledger does not:

curl -s "http://localhost:8000/ledgers?cursor=now&limit=1&order=desc" 
 | jq '._embedded.records[0].protocol_version'
0

The system in this state does not support any non v0 operation (after limited testing).

What are the additional steps to upgrading the protocol version?

I think the date that you used is in the future 1534550400 = Saturday, August 18, 2018 12:00:00 AM.

if you want it to happen right away, just use the epoch as per the documentation it's 1970-01-01T00:00:00Z