Re: Sounds like many sites will publish enough hints
Indeed. Any conviction with a custodial sentence exceeding 30 months, IIRC, is never "spent" insert current law. Additionally, if someone has more than one criminal conviction a Basic Disclosure check will show all convictions, spent or not whereas a single spent conviction would be filtered. Again, under current law.
In addition, no criminal conviction is "spent" when applying for a travel visa to various countries.