Does Permitted Development expire after planning approval?

Asker

I want to get Permitted Development (Lawfulness Cert) for building up the LEFT side of my house THEN get planning approval for the RIGHT side of my house as I fear putting the whole thing at once will increase chance of refusal but the left side would be fine under PD.

If I get planning permission to build up the right side of my house AFTER I get the PD cert for the left side of the house will it somehow void the PD lawfulness cert of the left side? (because circumstances different)

Doozergirl

There's always a slight possibility that one build could jeopardise the liklihood of getting the other.

If you are very worried, then some money spent on a planning consultant to advise on the exact order you should do things in could be a wise investment.