How many is too many ink drips?

Currently running a 3600 and suffering from intermittent ink drips. Mainly from either cyan or light cyan and when printing large areas of that colour resulting in a lot of costly rework. Been through our reseller who has realigned the wider blade and then replaced the whole assembly. Issue seem to go then return with no relation to what we're doing maintenance wise or age of the heads etc. Has anyone else had issues like this? I was told by our reseller that a certain number is expected but when I push them on this, they declined to give me that info. I'm currently tracking the relative humidity to see if there's a correlation between that and the frequency.