SuttaCentral
I sometimes wonder whether craving ( tanha ) is continuously present in some degree or form, even though we’re not always aware of it. For example bhava tanha ( craving for continued existence ) looks like something which is continuously present in the background, or in the unconscious.
What do you think?
“Bhikkhus, there are these three cravings. What three? The craving for sensual pleasures, the craving for being, and the craving for non-being. These are the three.”
SuttaCentral
Perhaps article on anusaya by Ven. Analayo could be of help
(The Underlying Tendencies).
sensual pleasure and bhavaraga is included in anusaya
I found this quote from the article interesting:
"Later Buddhist traditions struggled to reconcile the portrayal of the underlying tendencies, in the way it emerges in this passage, with the notion that wholesome and unwholesome qualities could not coexist in a single mind state. How can something decidedly unwholesome be in some form continuously present in the mind, even when no unwholesome mental condition is manifest and the mind is in a wholesome state?
Yet, the Greater Discourse to Māluṅkyaputta clearly shows that, from an early Buddhist perspective, the underlying tendencies are already found in an infant, even though that infant is unable to entertain the corresponding thoughts and reactions."
The ten fetters are divided into five lower that tie to the sensuous world, and five higher that tie to the fine-material and immaterial worlds. It is clear that there is a progressive reduction or refinement of craving, since number four to be abandoned is sensuous craving, and numbers six and seven are craving for existence in the higher worlds.
In pursuit of those and the higher goal of the severing of ignorance, positive craving is a necessity:
"‘This body comes into being through craving. And yet it is by relying on craving that craving is to be abandoned.’ Thus was it said. And in reference to what was it said? There is the case, sister, where a monk hears, ‘The monk named such-and-such, they say, through the ending of the fermentations, has entered & remains in the fermentation-free awareness-release & discernment-release, having known & realized them for himself in the here & now.’ The thought occurs to him, ‘I hope that I, too, will — through the ending of the fermentations — enter & remain in the fermentation-free awareness-release & discernment-release, having known & realized them for myself in the here & now.’ Then he eventually abandons craving, having relied on craving. ‘This body comes into being through craving. And yet it is by relying on craving that craving is to be abandoned.’ Thus was it said. And in reference to this was it said.”—AN 4.159 Thanissaro
Craving is described as a ‘flood’ and the simile suggests a constant quality to it.
My reading of the quoted passage is that the Noble Search results in Right Freedom from the craving for sensual pleasures, being or non-being.
This is corroborated by the ending of MN121:
There is only this modicum of stress, namely that associated with the six sense fields dependent on this body and conditioned by life.
So literally, just this “I gotta pee. Please excuse.”
Perhaps you could share on why you find it interesting?
In dhammapada tanha vagga, craving is also an anusaya
Just as a tree, though cut down, sprouts up again if its roots remain uncut and firm, even so, until the craving that lies dormant is rooted out, suffering springs up again and again.
Yathāpi mūle anupaddave daḷhe,
Chinnopi rukkho punareva rūhati;
Evampi taṇhānusaye anūhate,
Nibbattatī dukkhamidaṃ punappunaṃ.
If tanha would be sometimes completely interrupted, wouldn’t that be the end of tanha = liberation? So, automatically we have to suggest some mechanism to ‘bring it back’, which means that it was only ‘suppressed’ or ‘dormant’ after all.
In a mundane sense obviously tanha is not always the most dominant quality of mind. From the outside an arahant could still say “But your tanha is all over the place!” when we just enjoy a cocktail at the pool, thinking that not much is going on.
I suppose there could be temporary interruptions of tanha, while it is dormant. Alternatively it is always present in some form, but not noticed. Different types of tanha, some quite subtle?
Sure. I was referring to the situation while tanha is still present in its various forms. I suspect the 3-fold classification in the op is quite simplistic, and that there are many types and degrees of tanha operating, some continuously and some sporadically.
I think of tanha like a rope with many strands. If each strand of desire is taken away, eventually there is no rope.
Maybe it’s like a lava lamp. Sometimes dormant when the system is off, and sometimes with crazy shapes when the heat is on.
And an arahant lava lamp is…empty hot or cold? 
It has water only, no wax 
Craving,aversion and ignorance is completely eradicated only when we reach the stage of nibbana. Even though we might feel we are out of it in the grossest level ,as we progress it gets sutler &sutler. Continued effort of dividing, dissecting and penetration should be kept till we reach the final goal .this is what Buddha said.
The lava production has stopped because there’s no-more avijja.
The ignorance in the attitudes that lead to cravings are ‘this will be here for me to enjoy [permanently]’ 
.
be here: permanence
Me: self
enjoy [permanamtly]: sukkha/satisfying
Yes, it seems like ignorance is also continuously present to some degree, its like an underlying state of mind, deep-seated assumptions.
I think of tanha more like a force, a force of attraction, maybe like gravity or magnetic attraction/repulsion. “may the force not be with you” 