I must admit if one of my royals had enough excess saliva and was often yawning; especially with it's head pointing upwards like yours to concern me...I wouldn't be waiting around to see if he shed...I'd be booking a vets appt pronto!
Yes...the nose rubbing and soaking could well be because it is due to shed...but to me, the excess saliva is a completely unrelated problem; it certainly isn't linked to shedding anyway.
Excessive soaking also cries out ''mites'' so check him over for those. Incidentally mites make snakes shed much more frequently as they try to unburden themselves of the little critters.
But yes, I'd be getting it down the vets if there is excess saliva and the royal is yawning a lot and tilting its' head upwards like in your picture. They often do this with R.I's as they are trying to clear the airway.
Just to add...you shouldn't ever *need* to spray the viv when the snake is in shed...if the humidity level in the viv is already spot on...you shouldn't really have to do anything. To me, the humidity level is just as important on a day to day basis in getting the environment correct as the temperature is...and many people will agree on this.
Hope this helps.
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