Qualifying Period to ILR from DLR

[SFME]

My husband was granted his first Discretionary Leave to remain (non asylum) on 8 Feb 2012 valid until 7 Aug 2012. Then he was granted another DLR from 26 Aug 2012 to 25 Aug 2016. A third DLR was granted from September 2016 to September 2020. My question is:
When can he apply for ILR? He will obviously finish his 6 years of continuous residence in Feb 2018 but the actual Leave will expire two years after! What should we do?

[CMOSUK]

My husband was granted his first Discretionary Leave to remain (non asylum) on 8 Feb 2012 valid until 7 Aug 2012. Then he was granted another DLR from 26 Aug 2012 to 25 Aug 2016. A third DLR was granted from September 2016 to September 2020. My question is:
When can he apply for ILR? He will obviously finish his 6 years of continuous residence in Feb 2018 but the actual Leave will expire two years after! What should we do?

That is a bit odd, the second and third DLR grant was for 4 years each?

Normally you would have to have 6 years (minus 28 days) of DLR (starting from the first grant of DLR) to be eligible to apply for ILR.

Again, may I ask what it actually states on the correspondence in regards to grant of DLR? For example, my wife's HO correspondence states that after accrued 6 years of DLR she may be eligible to apply for ILR.

Need further clarification on this.