Out of curiosity I checked.
"For Gold, you’ll need to do your programme for at least 12 months if you’ve achieved your Silver Award, or 18 months if you’ve started at Gold level without doing your Silver – even if you’ve done Bronze. The big difference at Gold is you’ll also do a Residential section – staying away from home for five days and four nights doing a shared activity with people you don’t know.
– Volunteering section: 12 months – Physical and Skills sections: One section for 12 months and the other section for 6 months – Expedition section: 4 days/3 nights – Residential section: Undertake a shared activity in a residential setting away from home for 5 days and 4 nights.
If you didn’t do Silver, you must undertake a further 6 months in either the Volunteering or the longer of the Physical or Skills sections."
I don't think any reasonable assessor is going to complain if you miss a week or two during the 12 months (I was a guide leader so we met for 2 hours a week during the school term), but it is absolutely about the duration and not cramming it in.