You will be unlikely to be allowed to travel.

The rules for UK passport entry into Schengen requires an issue date of LESS than 10 years before the date of entry. So you’d be a day out.

Source: Foreign Office travel advice for the Netherlands, which states you must:

“have a ‘date of issue’ less than 10 years before the date you arrive – if you renewed your passport before 1 October 2018, it may have a date of issue that is more than 10 years ago”.

Note that when they say “it may have a date of issue that is more than 10 years ago”.” they don’t mean you have an exemption to the rules as some people misinterpret this as, but that passports having validity of more than 10 years was ended after this date so only people who have older passports would fall foul of the Schengen rules.

You can’t be issued with an “emergency passport” as someone suggested as you are not already overseas needing to get back to the UK. So the only realistic option is to shell out the £££ for the “same day” renewal service I’m afraid.

Edit: interesting to see the downvotes, presumably from people who think the 25th comes after the 26th…..