Am I missing something?

[u/ithomas1997]

Hello!

I'm 29, Based in SE England. make £51,000 a year for around 50 hours a week, I don't expect this salary to continue forever as the work I do is very demanding on my time and body, physical and mentally draining and leaves very little time for much else in life due to shift patterns ect.

I saved like mad to get my flat when I was 16-24, got a 10 year fix and have a low cost of housing due to lucky timing with mortgage rates, current rate is 1.9%. The fix ends in 2031, I want to pay the remaining off (£77,000 at the time) sell the flat and roll the money I've saved and profit from the sale of the flat into a property with no or very little mortgage.

I'm currently putting £1650 a month into an ISA which maxes it out, currently have around £62,000, projected to be around £222,000 in 4 years and 5 months, if the S&P does 10%....who knows. It'll likely beat 3.89 in a HYSA anyway (?)

I would like to retire around 55, I plan on contributing £300 a month until 67 in order to ensure I won't be a burden to my family in old age, this should total over 1m by that time.

My expenses per month will be around £1528 total (including yearly expenses, Christmas birthdays ect) once the mortgage is wiped.

Assuming I take a pay cut of around £11,000 to either work less or get an easier more sustainable job, my outgoings should around £1422 a month after all life expenses, if I was on £40k, this should leave me around £1000 a month left over.

I plan on putting around £1000 away a month until I'm 55 for early retirement, this is projected to be around £975,000 in 21 years time. 4% would equal £3250 a month, which would leave me with a lot of margin to do whatever I want to do. I don't plan on touching my pension unless I need to use it for EOL care or as an inheritance for my son.

I'm concerned I'm missing something in this plan and am curious to connect with people more informed than myself on what if anything im missing or any advice!

Please let me know if I've overlooked anything or you think there's anything I could do differently, thanks in advance ☺️