I made an automatic pumpkin farm, after going AFK overnight a found a bunch of pumpkins like this, not broken as they should be. (Farm has red stone torch above where pumpkin grows. Which powers the block it’s on, and red stone dust on a block behind it which powers the piston. Pumpkin updates torch.
On Bedrock edition, pumpkins, as well as sugarcane and some other crops, can sometimes grow in-between in-game ticks. If it grows in between ticks, then you won’t receive the block update, as updates only happen every tick. You can read more about this in the wiki. There’s no way around it outside of having a clock or daylight sensor to also power your circuit occasionally to take care of those random occurrences.
I solved this issue myself by having two daylight sensors give out one-tick pulses every time it changed from day to night and night to day. It’s slightly less efficient but it functions more consistently.