I am Spanish and have a 1987 "Leave to enter the UK for an indefinite period" stamp on an old passport. I have never applied for citizenship. I have lived in the UK since 1982, have a British husband and children, a NI number, an NHS number - including a prescription exemption card, a British driving license (1984), received Child benefit for all my children, have a degree from a British university, trained and worked as a teacher (retired early), paid taxes and will receive a state pension in 2027, and I have the right to vote in all elections other than General and Referenda.
Am I mistaken in believing that my status in the UK is secure indefinitely? Or do I still have to apply for a Permanent Settlement Status? The information on the gov.uk website is unclear.