Mortgage term and retirement query

LCM2021

Hi, 

I have seen some great advice and information shared on these pages. Would really appreciate if anyone could give any advice or ease my worries on my situation. 

I have got a full
mortgage offer from Santander today. I applied directly online and when I applied it said that they would only lend until my state retirement age (68). I was relatively close on affordability (they offered me a AIP for 140k and I needed 136k)  and so chose one of the longest terms they allowed given my age of 34 years and 1 month. (As of today it is 34 years and 4 months until I turn 68). My mortgage offer has an expiry date of October 2021 (6 months from date of application). 

My query is, should it take this long to complete (hopefully it won’t) is my mortgage offer still valid despite the fact I would be over 68 when it finishes? Or does the borrowing until pension age only matter as long as it falls within the time frame at the date of application? 

I hope this makes sense. Basically the mortgage offer states it is valid until October with no mention of my age. However if the purchase completed in September or October by the time my mortgage finishes I would be over 68.  I am unsure if therefore my offer should expire before October or I should ask them to recalculate this over a shorter term. Or am I totally misunderstanding something? 

Obviously if no-one knows the answer I will contact Santander and ask tomorrow. Just wondered if anyone on here had any experience  or knowledge of this before I am able to make the call tomorrow. 

Thank you in advance!