I would say set the routine for the horse ASAP, i would say exercise the horse within a few days after arrival (unless the horse is behaving dangerously/is severely distressed). Horses depend on a routine and if you establish one quickly (alongside giving the horse alot of love and care) will give them reassurance and the security in their new alien environment!! Hope this helps!!

as long as he needs he will let you know when he feels relaxed and comfortable Paganprince x

The mare i have on loan was with the owner from the age of two apparently, and she is now 9,, i moved her t a small quiet yard,, an she settles nicely and i was riding her within 2 weeks! If it had been a busier yard (like the one were in now) it would have taken her longer, but that was just my mare,, it may take longer to settle if your horse is highly strung, or may just slot in nicely withing days if it is more laid back. I thionk this is entirely dependant on the circumstance and the horse's personality. Just observe the horse and wait until it is well and truly settled before doing anything too heavy with it,, go with your gut and do what you think is right for your horse,, because you know it more than anyone else (:

Xx