Ok loss of separation, or not standard separation, or reduction in separation, this is not the important matter. I hope that you have understood the situation...
I give you also some references in your atc documents. UK AIP GEN 3.3.3, and UK AIP GEN 1.7.47, CAP 493 para 15.2.4 and attach E, CAP 413 appendix 1.
I continue to not understand if you use
"in practice" the land after procedure, when you use this procedure, and if you respect only its own condition, or ICAO reduced runway separation too.
