Renew Biometric card now or wait until spouse visa?

[Kadian]

I don't remember if I have asked this on here yet but...

My partner (US citizen) is currently on a post study work visa, after we marry in October and have all the relevant documents ready he will renew his passport straightaway to reflect his new surname. This means we will have to update his BRC to keep it valid.

I've checked on UKBA and it says:

"You must tell us as soon as you can if:

-you change your name (for example, because of marriage or by deed poll);
-you change your gender, legally or permanently;
-you change your nationality; or
-your facial appearance changes significantly.

If you change any personal details listed above or any details shown on your biometric residence permit, you must apply for a new permit within 3 months using application form BRP(RC). If you do not do this, you may have to pay a financial penalty of up to £1,000 or we may curtail (shorten) your permission to stay."

I can't seem to find any answers but does this mean within 3 months from the date of us marrying and acquiring/using new surname or 3 months from when we get his new passport with the new surname?

As we are applying for his spouse visa in December and this will require him to update his BRC again to reflect the new status I'm just wondering if it's ok for us to delay renewing the BRC after we get the new passport and just renew it instead when we get spouse visa sorted? Just to save us with the hassle of reapplying in such a small space of time.

The 3 month timeframe is my only concern as IF it means from the point we marry and obtain new surname(Start of October) then the 'cut off point' will happen whilst the spouse visa is in process(December), I don't know if we will get fined or if the BRC will be placed on 'hold' whilst UKBA process our spouse visa. But IF it means from the point we reflect surname change on his passport (If US passport takes 5 weeks to process then we'll get it by End of November) then we'll still be within the 3 month timeframe.

I also don't know if there will be any warnings if we get his BRC for surname change and then another one for spouse visa status a month or two later.

Any information or suggestion will be greatly appreciated, thank you