So having decided it was time to repack bearings and inspect our brakes I removed the first tire and my eyes went
!!
I knew this tire also had a very slow leak and now I certainly know why.
I also know now why they are described as "Westlake Bombs"!
This tire exhibited no tread wear, vibration or irregularities from the outside but quite obviously on the inside was a different story. All other tires appear to be just fine but they have now all been replaced with Sailuns which IMO are far superior in both weight and composition.
Would recommend to anyone else with these tires to inspect both inside and out and keep a very close eye on them for sure!