Hi and a raspberry siting question

Hi everyone, my first post here.
I've been an allotment owner for almost 10 years now and I think I'm fairly knowledgeable about things, having been a gardener for over 30 years, but what I want to ask is, when you plant a new row of raspberry canes, they say don't plant where they have been planted before, but is there a time limit on this, I. E. would it be OK after 5 - 10 years or is it a longer thing ?.
There must be a time limit or we'd run out of places to plant them.
It's just I want to put in some new canes but the area I'd like to plant them had raspberries on it when I took over my current plot about 7 years ago and I'm not sure if it will be safe regarding diseases.
Any help would be greatly appreciated.
Many thanks
Paul