Qualifying for an exception and actually receiving one are separate things, and the gap catches out applicants who assume the IND will spot their situation unprompted. There is also a point in the naturalisation process after which the request can no longer be made at all.
It's not automatic — nobody checks a box for you. You have to actively request the exemption (vrijstelling van het afstandsvereiste) as part of your naturalisation application, before the Koninklijk Besluit (Royal Decree) that finalises your citizenship is signed, and back it with documents proving you fit one of the recognised categories. A marriage or registered-partnership certificate covers that exception; a refugee residence document covers that one; for "my country won't let me renounce" or "my country strips it automatically anyway," IND works from an official, periodically updated list of countries and their nationality laws. For the more discretionary "reasonable grounds" category — disproportionate financial cost, loss of inheritance or property rights — IND assesses the specifics of your case rather than applying a fixed rule. The one hard deadline worth knowing: you can't go back and request this after you've already been naturalised, so if you think you qualify, raise it explicitly while your application is still open rather than assuming it'll get sorted out automatically.