Urgent! ILR SET (M) APPLICATION ACCIDENTAL OVERSTAY

Hi all! I need some advice as soon as possible please. I applied for ILR by submitting my set (m) application and paid the fee on 12 December 2018, however, as I was filling out the application I noticed that my leave had expired on the 10th of December 2018. The reason for the overstay is stupid, really. When I previously glanced at my BRP, due to a scratch on the card, I mistook the 0 in 10 for an 8 and thought that I had until the 18th to submit my application. I have booked the appointment to submit my documents for the 22nd of December, so my application and fee were 2 days late and my documents will be 12 days late. Should I proceed with my set (m) application? Do I need to make an FLR (FP) application? What would you guess the odds would be of the HO overlooking the accidental overstay? Will the fact that I have lived here for 5 years legally and with a clean record, the fact that I have two British children, 3 and 7, the eldest of whom is in shool here, and the fact that I am not currently employed so I wasn't working illegally work in my favour? I would really appreciate some advice as I'm incredibly stressed about this, and all due to my own stupid mistake.

Read the guidance for this scenario.
I think it’s 14 days but with good reason.
A covering letter detailing the reason or if it’s in the application somewhere..
hopefully it should work out!

Thanks! You're right, it is within 14 days with a very good reason. My concern is that my reason isn't very good. And, if my application is rejected, I don't know what course of action would be available to me.

A good reason is one that is exceptional and compassionate beyond the applicants control, i.e. serious illness, hospital stay, accident, family related death or illness etc. where supporting evidence and a cohesive letter would be submitted.

If your ILR fails as it is an out of time application, you will likely be asked to pay IHS and be issued a FLR(FP) Partner 2.5 year visa, possibly on the 10 year path to ILR.

Would I have to make a separate FLR (FP) application upon receiving ILR rejection? Would I have to leave the UK to apply for FLR (FP)?

Could I go ahead and withdraw my SET (M) application and submit an FLR (FP) application instead?

Also, is extant leave now required for SET (M)? If so, when did that happen? I can't seem to find the info from a Google search.

E-ILRP.1.5A.

In calculating the periods under paragraph E-ILRP.1.3., any current period of overstaying will be disregarded where paragraph 39E of these Rules applies. Any previous period of overstaying between periods of leave will also be disregarded where: the further application was made before 24 November 2016 and within 28 days of the expiry of leave; or the further application was made on or after 24 November 2016 and paragraph 39E of these Rules applied.

Have you thought abt going with what you have instead of varying or withdrawing right now.. maybe you get a kind caseworker who does take into consideration that you made a genuine mistake..What’s the worst case scenario?

Any news yet regarding your application. I'm in the same situation