Huawei sub-brand Honor today shared press invites to an event in London scheduled for the following date: 444+4x4x4+(4+4)/4+44/4. Do the math and you'll find that the sum equals 521, or rather 5/21, alluding to May 21, the date Honor has given for the launch of its next smartphone series.

The Honor 10 came with flagship-grade specs and was accompanied by two mid-range offerings — the Honor 10 Lite and Honor 10i — so it's a safe bet that we'll see corresponding models in the Honor 20 series. An Honor 20 Pro with in-display fingerprint sensor has also been rumored, which would make four models in total and probably explains Honor's cryptic equation.

We can expect to see Huawei's top-of-the-line Kirin 980 chip in the two more expensive Honor 20 phones. They're also likely to feature triple rear camera modules with 48MP main sensors, similar to the View20 that impressed in our review earlier this year. The image of Tower Bridge at dusk and at night possibly hints at an improved night mode, too.