The OP's question was specific to an extended connection time in AMS so likely to be specific to KLM.
A number of years back I had a business trip to FCO which was PDQ followed by a day of business in Netherlands.
So I booked KLM BHX/AMS/FCO/AMS/BHX and no matter how I tried I couldn't get a long enough connection on the return in AMS to complete my day of business there without paying an arm and a leg for it, upon enquiring I learned that longer than a few hours in AMS then KLM charge for it.
I threw the AMS/BHX leg of my KLM journey away and rebooked that with BMIbaby.