Correct, I skipped PL4 and PL6, i.e. I had PL 3 and am now running PL5. Very cost effective for me as when I went from PL 3 to PL 5 DxO considered me a ‘current user’ so the upgrade cost was a sizeable reduction on the ‘new user’ price. The same is true for me this year, my upgrade price for PL7 is much less than the ‘current user’ price.
BUT…
This policy may not hold true in the (near?) future. See my post here for why I am speculating like this:
https://forum.dxo.com/t/be-aware-dxos-upgrade-pricing-policy-has-changed/34923
NB note my emphasis on ‘may’ and ‘speculating’.