[frik]

Good link. Nevertheless HTTPS/HTTP2/TLS/bcrypt/MD5/SHA-256/AES/etc need an upgrade/replacement to be ready for day X, so the internet isn't really prepared yet. Also mind all the previously already leaked encrypted data got harvested by bad actors and is waiting in archives to be easily readable on day Y.

[wbl]

There is a plan. There already are postquantum encryption schemes (and drafts to use them), and we can wait with signatures for a while. NIST will be making recommendations soon.