For the OP - the reason we can't say with any certainty the impact a solicitor might have is that whilst we see a lot of people in this forum who are in bother with TfL, not many seem to take the solicitor route and of them very few come back afterwards and tell us the outcome, so we just don't have enough data to have any confidence in what might happen.
Engaging a solicitor will be expensive (maybe a grand or so) and whilst they absolutely won't make things any worse, there is no guarantee of success.
If I was you I would look up some of the specialist solicitors in this area (a search of this forum will find you a list, Manak is one that I recall) and see if you can get a free initial consultation, and if so give them a two minute 100% honest overview of everything (what you've been doing, how you've been doing it, for how long, how you got caught, what TfL have said so far) and ask them honestly to give you a view on how likely it is they can avoid a prosecution.
Useful info / advice here
Here is a list of some solicitors that have been mentioned on the forum before:
Manak Solicitors
Fare Evasion Solicitors | Kent & London | Manak Solicitors
Makwanas
Fare Evasion Solicitors London | High Success Rate | TFL Solicitors
www.makwanas.co.uk
http://www.grayhooperholt.co.uk/default.asp?id=30
https://penmansedgwick.com/fare-evasion/
Given this case is likely heading to court - the best advice for the OP might well be to prepare for that. The most thorough post on preparing for what will happen in court that I've seen on here (IIRC in relation to a TfL prosecution case) was provided by @island not that long ago - here is a copy of it:
When attending court, you should bring with you copies of all paperwork you have received, and a form MC100 income and expenditure form. If there is anything on paper that you will want to give the court, such as a statement, you must have
six copies of each document:
- Three for the magistrates
- one for the legal advisor
- one for the prosecution
- one for yourself
It is strongly recommended to dress formally. Where possible, gentlemen should wear a dark suit, tie, and formal shoes, and ladies should wear a suit with jacket, a formal top and skirt/trousers, or a dress, nothing too revealing, formal shoes and tights or similar should be worn. Jeans, trainers, open-toed shoes, anything bright, gaudy, or with slogans of any sort should be avoided.
At the court, you should make sure to arrive in good time before the time indicated on your summons. You will need to pass through security checks, which will typically include a walk-through metal detector and a bag search. Certain items are prohibited – check the Courts Service website.
Most courthouses have a number of courtrooms. You will need to check a noticeboard to see which courtroom your case has been assigned to. Staff can point this out. Speak to staff to identify yourself as a defendant.
You will probably have a fair bit of waiting around to do. Bring a book/magazine. You can use your phone whilst waiting in the court building but it should be on silent/do not disturb when in the court room itself.
When you are called into the courtroom, staff will indicate where you need to go. Do not sit down until invited to do so. You will likely have three magistrates sitting at the back on the highest level, with a legal adviser in front of them. (It's possible but unlikely that these four will be replaced by a single district judge.) Towards the centre of the court will be one or more prosecutors – solicitors representing TfL.
The legal adviser will ask you to confirm your personal details (name/address/DOB) and from there they will step you through what needs to be done – you'll likely be asked to confirm your guilty plea and then explain your mitigation. Mitigation means the reasons you are saying the court should punish you less harshly, or not at all.
After that, it could go off in several different directions, so I can't predict beyond there, all I can do is remind you that the court understands that their process is unfamiliar and will be happy for you to ask clarifying questions if you are unsure about anything. If you end up with a fine, you'll be asked if you can pay it right away (which really means within 28 days) or if you need to pay in instalments; they'll usually want it paying within 12 months. A letter will be sent to you with instructions on how to pay online, over the phone, or with a barcode at a "Paypoint" (convenience store).
Finally, don't be tempted to call anyone "your Honour" – that phrase isn't used at Magistrates Court. The magistrates collectively are addressed as "your Worships". Anyone else, including magistrates individually, should be addressed as "sir" or "madam" (not "ma'am").