Well, I don't know fellas? All I can do is try to help without knowing how you all are doing things.
After reading that this thread continuing, I happened to have my Banish 30 sitting here, I had swapped rifles and suppressors in my bag from Banish 30 to Banish .338 one piece. So I picked my Banish 30 up and by hand without strain loosened the end extension. I would have to look through my logs, but it has been on 2 .300 WMs and maybe 75-100 rounds since clean. I will not clean until 150-200.
No special cleaning solutions or sonics. Hoppes, sometimes acetone and baffles in SS tumbler.
No special tools.
I do not overheat or abuse my equipment.
I do not remove the end cap before the extension, to prevent deformity and binding.
I use a couple little dots of high temp synthetic grease and reinstall by hand.
I use only Banish products from Silencer Central, I waited a year for my .338 to come to market, and could have purchased any other brand I wanted. Their customer service is great, and the product is excellent. If anyone has a question, I will try to help best I can, but is difficult not knowing all the variables.