What are these new checkpoints I am getting?
It happens when you delete a screen.
Ok thankyou
The screen keeps on that checkpoint. If you want to put the screen back, you have it on the checkpoint. add all the blocks that you added after the screen deletion to backpack and paste all them on the checkpoint.
Thankyou. no I deleted them purposly
Ok 
If you're deleting the screens and don't want the checkpoints, you should uncheck the option to create a checkpoint prior to deleting the screen:
thankyou i will do this next time onwards