So a lot of people seem to be giving morally related advice, I will try to stick to the facts:

Assuming you have been caught, you will receive a SP30 fixed penalty notice (FPN). This will be a fine and 3 points. If your local police force offers speed awareness, they may well offer you this. This results in no points but a slightly more expensive course fee + a few hours of time wasted.

For reference, you are correct about the 6 points ban in two years.

For everyone else giving information without checking, speeding infractions are dealt with in 3 bands for sentencing purposes. Band A Speed limit 10% + ~9 is a FPN, 3 points and a fine (or driving speed awareness).

Band B is ~ 10mph above the band A upper threshold. This is a court appearance, a maximum of 6 points + a fine or a 28 day ban.

Band C is above the upper band of Band B (ie 101mph for motorways). Instant 3 months ban. If you are a new driver you will need to resit your test. Court has the power to increase ban length and fee as they see fit (within certain limits).

In all cases and whatever the outcome, you must inform your insurance as this is a material change in your insurance risk. Your premium will go up and young drivers will likely find some insurers won’t even insure them after 1 FPN SP30/or SP50. Only report it if you get a Fixed Penalty Notice. If you didn’t get a notice within 14 days of the infraction then it’s not valid.

If you don’t get a notice then take the advice of the rest of this thread and take your foot of the accelerator. Speeding in a 30 is the quickest way to kill someone. I believe the rough stat is at 30 if you hit someone there is a 60% chance they will survive. At 40mph, the survival has dropped to 40%. For ease sake that means for each 1mph over the limit you go you increase the chance of manslaughter by 2%. Not worth it.