In detail
The High Commission's document words it as “minimum validity of six months as on the date of submission of application for visa”: the clock starts on the day you submit, not the day you travel. This is where people most often come up short: they check that the passport is valid six months past the travel date and find it falls short at submission. Work backwards six months from the expiry date; you must submit before that. If you are short, renew first. Renewals take time, so check at the start of your planning.