First of all, all the reports talk of "suspicion" of drink driving and "allegedly" travelling at 100mph. At this stage, he is innocent until proven guilty. Reports also say he is to appear at a police custody suite where, I presume, they will decide whether to charge him. Clearly he has not yet appeared in court.
If he has been speeding at between 101 and 110 mph on a motorway then the court can fine (based on earnings) and disqualify for between 7 and 56 days or put 6 points on the licence. If the speed was above 110 mph it is in the magistrates' discretion to increase those penalties.
If he was driving over the drink/drive limit then the punishment at the lowest end of the scale will be a hefty fine and a ban of between 12 and 16 months. At the highest end of the scale the punishment will range from a high level community order to 26 weeks in prison plus a driving ban of between 29 and 36 months.
But, to repeat, at this stage nothing has been proven.