Use option 'R' to restart ARKnode, but I'd just use option '4' in ARKcommander to rebuild from snapshot it will be quickest.
I've done that few times and I just did it again.
[inf] 2017-04-03 10:31:46 | Found common block 134268 with http://167.114.29.56:4001
[inf] 2017-04-03 10:31:46 | Loading blocks from: http://167.114.29.56:4001
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"31.187.70.176:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"188.166.174.198:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"108.61.170.190:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"185.170.115.129:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"45.55.186.177:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"163.172.139.221:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"79.137.83.181:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"167.114.43.48:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"137.74.11.163:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"163.172.182.76:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"137.74.79.169:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"204.10.184.238:4001"}
[inf] 2017-04-03 10:31:46 | Blockchain not ready to receive block - {"id":"4827711618949670116","height":134391,"lastBlockHeight":134268,"peer":"104.131.128.207:4001"}
[WRN] 2017-04-03 10:31:53 | Blockchain rebuild triggered - {"date":"2017-04-03T10:30:09.772Z","secondsAgo":103,"stale":true,"rebuild":true,"height":134268}
but "lastBlockHeight" still doesn't move:
[inf] 2017-04-03 10:39:07 | Blockchain not ready to receive block - {"id":"3656603720351277510","height":134446,"lastBlockHeight":134268,"peer":"37.59.129.170:4001"}
[inf] 2017-04-03 10:39:07 | Blockchain not ready to receive block - {"id":"3656603720351277510","height":134446,"lastBlockHeight":134268,"peer":"51.255.105.54:4001"}
[inf] 2017-04-03 10:39:07 | Blockchain not ready to receive block - {"id":"3656603720351277510","height":134446,"lastBlockHeight":134268,"peer":"5.39.53.52:4001"}
[inf] 2017-04-03 10:39:07 | Blockchain not ready to receive block - {"id":"3656603720351277510","height":134446,"lastBlockHeight":134268,"peer":"94.176.237.172:4001"}
[inf] 2017-04-03 10:39:07 | Blockchain not ready to receive block - {"id":"3656603720351277510","height":134446,"lastBlockHeight":134268,"peer":"45.55.66.111:4001"}
[inf] 2017-04-03 10:39:07 | Blockchain not ready to receive block - {"id":"3656603720351277510","height":134446,"lastBlockHeight":134268,"peer":"185.5.55.53:4001"}
[ERR] 2017-04-03 10:39:09 | Rejecting invalid peer: 167.114.43.46 #/ip Object didn't pass validation for format ip: 167.114.43.46
[ERR] 2017-04-03 10:39:09 | Rejecting invalid peer: 167.114.43.47 #/ip Object didn't pass validation for format ip: 167.114.43.47
[ERR] 2017-04-03 10:39:09 | Rejecting invalid peer: 167.114.43.48 #/ip Object didn't pass validation for format ip: 167.114.43.48
[ERR] 2017-04-03 10:39:09 | Rejecting invalid peer: 167.114.43.50 #/ip Object didn't pass validation for format ip: 167.114.43.50
[ERR] 2017-04-03 10:39:09 | Rejecting invalid peer: 167.114.43.49 #/ip Object didn't pass validation for format ip: 167.114.43.49
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"162.243.49.63:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"167.114.29.47:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"167.114.29.53:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"167.114.29.52:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"178.238.227.176:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"137.74.79.174:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"51.254.118.236:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"5.135.102.93:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"52.178.31.253:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"51.15.133.54:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"137.74.11.166:4001"}
[inf] 2017-04-03 10:39:15 | Blockchain not ready to receive block - {"id":"8844870702882560353","height":134447,"lastBlockHeight":134268,"peer":"45.32.159.16:4001"}