Paddy
Welcome to the forum.
I think it's fair to say you are at risk of failing the CDT. I am assuming you are a HRO coming to the end of a driving ban?
The CDT is used by the DVLA to determine alcohol levels in the human liver. Best practice is to abstain for as a long as possible - in my case I hadn't consumed alcohol for 15 months prior to my CDT last year.
The DVLA can vary the CDT limit for each candidate, but as a benchmark - if you have been placed in the category of alcohol 'misuser' or 'dependant' the DVLA expect a result of less than 1.5% for your reading. Mine was set at 1.3% and the reading was 0.9%.
If you was to take part in a CDT tomorrow after a cheeky vodka orange on Friday, you would probably be looking at a CDT of at least 3.0+% because the alcohol hasn't digested through your system. The human body takes 14 days to cleanse itself of any alcohol toxins after the last drink.
You have to be honest with yourself - which is more important - having a drink or getting your licence back?
Given what you have a disclosed here, I would be tempted to reschedule your
CDT test for next month and have a solid four weeks (minimum!) off the booze.
The cost of a HRO medical is £100+ (I can't remember the exact figure) and you might as well throw your cash down the drain if you've been on the vodka just a few days before!
The DVLA will automatically fail you and you will not be able to re-apply for your driving licence for a minimum of six months - during which you will not be able to drive. After that you will have to pay (yet again) for any further HRO medicals until you pass.
This forum is a fantastic site for advise and information, but members are only here to help those who are helping themselves. You need to at least realise that getting your licence back isn't a walk in the park and takes a lot of effort and will power. Sadly it seems, these are areas you need to focus on before you can get back on the road.
CJ