No aggressive chemicals:
its complete lack of ammonia or aggressive chemicals make Caffélatex benign even with very sensitive latex inner-tubes (like those found on professional level cyclocross tubulars, for example). Caffélatex is perfectly compatible with tubulars with butyl tubes or tubeless-tubulars construction (like Tufo).
Long expected lifespan:
if used inside tubulars, as their porosity is very little compared to a tubeless tire, Caffélatex lifespan (as a liquid) will easily exceed one year. This also applies to the lifespan of Caffélatex used as preventative inside simple inner tubes. Usual care with CO2 cartridges is highly recommended.
When it’s dry:
once it’s dry, Caffélatex can’t be removed from the tubular, but additional liquid Caffélatex can be added, to restore effective puncture protection.
There’s no problem in adding more Caffélatex, and there’s no negative interaction between dried-up (or partially dried-up) and fresh Caffélatex.
How to check it:
the best way to know there’s still liquid Caffélatex inside a tubular is letting the tubular sit for some minutes with the valve at the bottom then, without moving the tubular, opening the valve and gently squeezing the bottom of the tubular: if some CL gets out of the valve (or there’s some noise of liquid while squeezing the tubular), then the puncture prevention is still active. Be sure to clean the valve after that (just inflate with a pump, or remove the valve mechanism and dry the black rubber seal with a rag).