You have been given a bit of rough treatment from other members of this forum - and frankly with justification. I do hope, for your sake, that Luton Airport Parkway didn't feature much in your travel plans. But let me give you another way forward for you to consider, only you can judge if this how you want to go through with it.
Perhaps you can see that getting repeated and unplanned demands for £800 from assertive bailiffs for a £20 fare dodge is a bad deal. They will get their money, they will seize your income, future income, car, possessions until the debt is paid, that is their job. There is an unknown quantity more of this coming, and perhaps you think "this is crazy". It is. There is another way to handle this, so long as you are genuinely going to bring this to an end.
a) buy - from today - the right ticket each and every time, and keep records of this. It's quite OK to buy the cheapest correct fare on the best railcard, and there are all sorts of ways to legitimately save money. Elsewhere in this forum you can get the rail brains on the topic and they may pleasantly surprise you.
b) write a genuine, honest letter to EMR Prosecutions in the first instance saying "Yes, I am a habitual fare dodger, but this has to stop. I want to do the right thing to pay all my debts to EMR, and own up to all the mistakes I've made. I've used false names and addresses here, so it's going to be difficult, but I am willing to sit down with you to work out everything as accurately as possible by sharing everything I know about this".
It may be that EMR will ignore it, or find it difficult to process or even believe, but equally it is in their best interests to help resolve this. Anything that has got to Marston is more problematic but it maybe that you can stop HMCTS sending more fines to them, since they will surely find you.
