When changing PCEP configuration through RESTCONF (via blueprint), the PCEP topology provider was not properly restarted. New PCEP session will not be able to established because the old PCEP topology was not removed from network topology.

Karaf log attached.

2017-03-30 09:37:11,798 | INFO | entLoopGroup-6-4 | PCEPSessionImpl | 243 - org.opendaylight.bgpcep.pcep-impl - 0.6.2.Boron-SR2 | Session /10.18.133.61:4189[1] <-> /10.18.133.205:21090[1] started
2017-03-30 09:37:11,803 | WARN | entLoopGroup-6-4 | DefaultChannelPipeline | 103 - io.netty.common - 4.0.37.Final | An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception.
io.netty.channel.ChannelPipelineException: org.opendaylight.protocol.pcep.impl.PCEPSessionImpl.handlerAdded() has thrown an exception; removed.
at io.netty.channel.DefaultChannelPipeline.callHandlerAdded0(DefaultChannelPipeline.java:590)[104:io.netty.transport:4.0.37.Final]
at io.netty.channel.DefaultChannelPipeline.replace(DefaultChannelPipeline.java:534)[104:io.netty.transport:4.0.37.Final]
at io.netty.channel.DefaultChannelPipeline.replace(DefaultChannelPipeline.java:475)[104:io.netty.transport:4.0.37.Final]
at org.opendaylight.protocol.pcep.impl.AbstractSessionNegotiator.negotiationSuccessful(AbstractSessionNegotiator.java:35)[243:org.opendaylight.bgpcep.pcep-impl:0.6.2.Boron-SR2]