This time, get it right.
The uplift and re-lay of a patio or driveway should be determined on how it looks, the tell tale signs are always there.
If it has sunk then maybe the sub base needs looking at; if the blocks have spread and opened up then the edging concrete may need to be re-set. If it has sunk around the drains or manholes then possibly there may be some erosion of bedding sand and a membrane is needed. If block paving is generally quite good to look at it could be a simple answer of uplift, re-clean and re-lay.