Here at the tip of africa we have to use behind twice ( cause management thinks us twice as dumb i think), but only on a landing conditional and we have to also confirm that the trafic at the hold has the landing in sight, bit dumb but very cautious. A conditional line up in sequence to others on the taxiway is basically "line up in sequence/turn" (sequence is the preferred new word that managment wants us to use but the old dogs use turn). We normally hold traffic at the CAT II hold and TWR will take them to the CAT I hold in departure sequence but if all are already on the same taxiway or already sequenced by GMC then "line up in sequence" is used meaning that they can cross the CAT II hold to the CAT I and as the previous starts thier take off roll move on to the runway. Personally I would prefer acft to stay at the CAT I hold till the preceding starts to roll but if you do nudge forward its your windscreen that gets pock marked by any debris that could be thrown up. Also if you don't nudge forward and i Need to cancel a line up clearance its easier if you are still behind the CAT I hold
And we don't have a RWY 37 in africa either