Personally, I don’t see the issue with this.
All that’s been done is you saved a quote from two months ago. The value of the phones has dropped in the past two months, I think they’re right to be able to requote as you haven’t confirmed order with them.
I’m my line of work, if I quote someone £1000 for a job. The parts are £500 from supplier and the labour is £500. They come to me two months later and want to book in but the parts are now £750 from supplier, I’m not going to honour the £500 am I?
Hence why they run a policy where they honour checked out prices, as long as the device is received within 21 days. I think it’s naive to expect them to honour prices from two months ago when all that’s been done is a quote.