Morning Katy.
Yes, you can still drive until your court appearance in January. With blowing 79, you could be looking at a ban of around 18-24 months or more as it is double the drink driving limit. However, if you request the drink driving reduction course at the Magistrates you can get the ban reduced by 25%.
A good thing working in your favour, is that you have just fallen below the benchmark of becoming a High Risk Offender, so at least you won't have the miather of the DVLA medical team probing into your medical background when the time comes to get your licence back.
CJ