More frequently than now my sugarcane farm, inspired by silentwhisperer, has come across a bug in the piston clock that moves the left side of the waterlogged stairs back and forth. So far it has only been the left side (from the lever side) but basically it creates a "reverse ghost block" that can act as air preventing any interaction. I cannot mine it and trying to will only remove the block directly after it. The piston will not push the block whatsoever either despite being within push limit.

The only way I've managed to fix it is by moving the opposite piston one block forward to push the whole row forward another block and thus bringing back the staircase. Initially I thought this was due to having the redstone repeater in the redstone clock powering the farm on 1 tick but I also tried it on 2 ticks and it soon broke. I'm not sure if it's a big with the repeaters and delays or not. I also rechecked the block limit and it's within the 12 block push limit.

This was never an issue in the previous 1.14.30 version as no matter how much I'd have the farm running, on 1 or 2 ticks, it never broke. My version updated yesterday and this was the only instance this had happened.

In terms of how to recreate, as mentioned before, the sugarcane farm by silentwhisperer is probably the best way to recreate this, or at least the piston clock mechanism itself. The farm I made is long enough for 20 blocks of sugarcane as opposed to silent's 22, which shouldn't effect it as I've also had this work with 10 blocks of sugarcane. I've uploaded short clips in 4 parts.