I was trying to make a latch to launch 1 silo then the other, by reading contents and launching when science packs hit 1000
However, on a seemingly random basis, one silo or the other would not output 1000 before launching and instead output 992 for example, then 0 on the next tick.
This resulted in ...

Thanks for the report. While not strictly a bug (at the time rocket silo control behavior updates there are no items in rocket silo) i see having content provided useful, so starting from 2.1.20 a rocket silo will send content of attached cargo unit for 1 tick which should make your use case ...