The 'Chained to the Rhythm' hitmaker changed all of her social media profile pictures to a blinking-eye graphic with the date written behind the eyelid over the weekend.
The same visual was posted on a massive billboard in Times Square, New York on Sunday (14.05.17).
It is also a preview of a song with the lyrics, "Will you be my witness? I am just looking a witness in all of this. Looking for a witness to get me through this", heard.
The pixie-haired beauty's fans have been guessing that the eye is alluding to Katy announcing her new album or a single called 'Witness'.
Earlier this month, Katy wore a veil with the word on it to the Met Gala Ball.
The track would follow 'Bon Appetite' and the pop superstar was recently confirmed to feature on Calvin Harris' forthcoming album 'Funk Wave Bounces Vol 1'.
The 32-year-old singer famously fell out with the 'Shake It Off' hitmaker - who Calvin dated for 15 months until June last year - in 2012, after she claimed Katy pinched three of her backing dancers from her 'Red' tour.
However, despite their disagreements and after Taylor allegedly wrote her 2015 song 'Bad Blood' about Katy, she said she won't be addressing her feud on her own record.
She said recently: "I think [my new album is] a very empowered record. There is no one thing that's calling out any one person. One thing to note is: You can't mistake kindness for weakness and don't come for me. Anyone. Anyone. Anyone. Anyone. And that's not to any one person, and don't quote me that it is, because it's not. It's not about that."