FROM EASA Certification Specification ADR-DSN.M.710 Taxiway centre line lights
"Where necessary to denote the proximity to a runway, taxiway centre line lights should be fixed lights showing alternating green and yellow from the perimeter of the ILS/MLS critical/sensitive area or the lower edge of the inner transitional surface, whichever is farthest from the runway"
The inner transitional surface (or obstacle free zone) can be as close as 60m from runway centreline for Code E aircraft types (eg B777) or 70m for Code F (eg B747-8 or A380) so if the ILS sensitive area is not affected at this distance then the inner transitional distance could be used. Some ILS systems are extremely accurate and if technical safeguarding is carried out the results may show that ILS at some airports is not affected when within a portion of the green/yellow lights. So it mustn't be assumed that when within the green/yellow lights that it will be within the ILS sensitive area. The key thing is that the aircraft continues to move when vacating the runway.