Mortgage reducing payments?

Cornholio_2

I must apologise first for probably coming across as a bit financially stupid, but I need some advice on our quest to be mortgage free asap...
Currently mortgage is fixed with Nationwide, 5.18% ends May this year and we go back to 2.5% BMR. Means payments drop from 754 to 605 pcm on approx £100k outstanding. I've been overpaying £499.99 per month via online banking...don't want to risk hitting £500.00 in case I mistakenly overpay and get hit by their ERC for a penny or whatever....
In June we plan to put in £30k, and I'll be putting in £1k as a regular monthly payment(well, that's the plan....4yrs) from then on in.

What I need to know is will our "required" payment from this point in be recalculated each month? Ie at £70k owed it should be £420 or so pcm, and with each additional £1k will that number drop monthly?
The Nationwide blurb says something along this line if you overpay the max £500 pcm during the fixed term?
Or am I missing something completely??!!!:eek:

muddywhitechicken

No, if you overpay by £500 or more (once your fix ends) you can choose whether to reduce your monthly payment or keep your monthly payment the same and reduce your term