Starting with the 1.18.10 update this Tuesday, I have had multiple users from multiple servers report the return of "block lag" or reappearance of blocks when mining them quickly.

Initially we thought it may have been a return of the old Unbreaking bug (where tools with unbreaking were experiencing block lag on servers but ones without them were fine), but testing with many types of tools didn't fix it.

This is more common for users with a ping of over 100, however, these same users (myself included) weren't experiencing this at all prior to 1.18.10, so I feel ping is only aggravating the issue, not causing it.

In short:

as of 1.18.10, instamining blocks on a server results in the blocks reappearing in ways that I have not witnessed since 1.15.

Attached: short video taken on PE showing sand blocks reappearing after being mined; I'd estimate about 10-20% of the blocks are doing so. Same issue has been experienced on Win 10. Have not heard from any console players yet about it.