As per my understanding, normally, If spot moves up by 100 points, ATM option premium goes up by 50 points. so the delta is 0.5 for ATM options. The Delta value increase and decrease for OTM and ITM options based on the distance or difference from spot.
My doubt is, will delta increase and decrease with same value for options with current month, next month, far month expiry? As the time decay (theta) will be different for each month expiry.