LDR versus actual landing distance
The LDR is the actual landing distance x 1,67 for dry RWY and actual landing distance x 1,92 for wet RWY unless dry would be the greater number.
My understanding of EU OPS is as follow: those rules are to be met in the planning phase of the flight or for an inflight replanning (change destination).
Inflight when preparing the landing we have to look for the actual landing distance. In this phase of the flight we have to consider a lot of things we canīt consider in the planning phase prior the flight. For exampel the actual landing weight of the aircraft (may be higher than planned because of less fuel burned etc.). The now calculated actual landing distance (AFM - no factor) has to be within in the factored LDR as above.
The result is that the margin could now be less than within the planning phase. It could be zero (not good). The actual landing distance could be greater than the LDR as well (no landing allowed).
Am I right?