A380 approach spacing at EGLL

[LHR27C]

Dear all

What is the current spacing applied to the A380 on final approach at LHR? I'm thinking in particular the evening arrival, SQ318, which presumably would be at a time of day when increased spacing would cause more problems than the early morning arrival of SQ322. From a look at some of the SBS logs, it would appear certainly at times in July the A380 was arriving with a 2-3 minute gap between it and the next aircraft, even when the following a/c was a narrowbody, for example:

SIA318 SQ318 9VSKE A388 WSSS 1746 301 27R
AZA5P4 AZ208 IBIXL A321 LIRF 1748 208 27R

SIA318 SQ318 9VSKE A388 WSSS 1754 303 27L
BMA3KD BD130 GMIDS A320 EIDW 1757 178 27L

Or perhaps just this is SBS being inaccurate?

Anyway, would be interested to know what nm spacing this equates to and the current procedures for A380 wake vortex separation at EGLL.

Thanks in advance.