Update: After running a few more test scenarios, I found out that, when deleting a letter from the input, the cursor moves its position, but hitting backspace/delete is acting upon the previous position. So, using the same example:
GHI1234 -> if I delete "I", the cursor moves to between 1 and 2. So, if I hit the delete key, I'm expecting that it will delete number 2, but instead, it is deleting the 1 (which is actually what was expected if the cursor had not jumped from its position).