I'd be interested to know your process.
sadly my issues with mounted RC papers have taken 1-3 years to reveal themselves and have never failed to do so.
while testing, before selling, you might consider:
expose your sample to direct intense sunlight (like outside where it can get properly hot)
see if you can simulate dramatic humidity and temperature changes
see how things stand after some environmental abuse. my past experience humidity and temperature are precipitators of delimitation. usually in the form of ugly bubbles.