In your defence, the Jeppesen guides only answers this question by exclusion, rather than being explicit. (Standing by for someone to find it phrased better!)
United Kingdom - Rules and Procedures - LEVEL RESTRICTIONS When a departing aircraft is cleared to climb directly to the cleared level without complying with the published vertical restrictions on the SID, ATC will include the word 'now' in climb instructions.
However the symbology on the chart does reinforce this with the bars above and below 6000.
I have to have a good revision of the non-standard US terminology whenever I fly there and find it equally baffling at times!!