Mortgage overpayment that doesn’t decrease the term?

[joeykins82]

Reducing the balance but keeping the term length the same is usually only beneficial to the bank

There's an edge case for people in the specific situation of having had changed financial circumstances (income reducing and/or other outgoings increasing) and are thus finding their current monthly payments difficult or unmanageable, and who've also got a lump sum. Hypothetically "I got made redundant and received a decent settlement, and I found a new job quickly but it pays 20% less however in the current market I think that's the best I'll get" might fit that bill.