To verify which SMB version is in use for a specific fileshare/connection, run the following powershell command:
Get-SmbConnection |select ShareName, Dialect
You can run this command on both the client and the server. A client/server connection will use the highest version supported by both client and server. If the client supports up to v3.02, but the server is only able to support v3.00, v3.00 will be used for the connection.
The Get-Smbconnection commandlet supports a several other outputs, use select * to list them all.
This is from a Win2012R2 client, connected to a share on a Win2012 cluster with multichannel support.