[p3n1s]

Aerodrome traffic circuit is the ICAO term for traffic pattern, which is it what it is called in the US (it may be in the glossary but the point is that manual uses "traffic pattern" repeatedly). And this "traffic circuit" you refer to is almost always a VFR thing, as IFR approaches use specific charted procedures that generally do not end with a traffic circuit.

https://skybrary.aero/articles/aerodrome-traffic-circuit

[ExoticPearTree]

Aerodrome traffic pattern is completely different from holding patterns. And this is what LH was instructed to do, keep holding. Holding patterns are published for all airports and usually planes are stacked on those holding patterns and they are emptied FIFO style. Busier airports have multiple holding patterns to accommodate a large number of aircraft in case of on ground emergencies.

[p3n1s]

Sure, but GP stated wrt traffic patterns, "This is independent of whether the approach is IFR or VFR." which is not the case. For IFR, as was the case here, the LH was looking to execute an IFR approach, not ever enter the aerodrome traffic circuit.