Don't Wait If You Need a Phone Now
Don't wait if you need a phone right now. There are so many excellent options available and the P30 is still at least 3-4 weeks away.
If you're needing something now, it might be worth buying something today, and trading it in come 6-7 months later. Especially with all the trade-in deals available these days. The Mate 20 Pro is a great phone. It has a stunning screen, capable cameras, the latest version of Android, and it'll get Android Q faster than most Huawei phones too.
That said, following the March 26th launch event (confirmed) we're hearing these phones will be available on around April 5th. So, the wait is almost over.