The Mexican newspaper El Universal runs several news items throughout the day across all its social media accounts. Of those, one particular practice that recently caught my attention is their use of this hashtag: #BajoReserva.
If I have noted correctly, they run at least one tweet with this hashtag every day. The piece with this hashtag also carries this tag on other platforms such as the El Universal app, its Facebook page, etc.
What could be the best way to interpret this expression in this context? I know the phrase literally translates as under reservation but in the context of news, it hardly makes any sense.