I really appreciate your urgent advice! I missed my visa expiry date which was 14/02/2019. For some reason I remembered a wrong date in April. Now I have overstayed 31 days.
Here are the details
type of permit: spouse leave to remain
expired: 14/02/2019
place and date of issue: UK 12-08-2016
My husband and two kids (4 Years and 16 months) all hold British passport. My case was straight forward but i messed it up by forgetting the expiry date

Also, I applied for ILR in 2016 on the basis of 5 years HSMP but got rejected because of discrepancy in tax submissions. My 10 years in UK were completed last year but the solicitor suggested that i should not apply for ILR on 10 years basis because of previous tax discrepancy rejection.
Please advice what shall i do next.
Many thanks,
Ambreen