If a collateral is not delisted, it will be rolled over to the next expiry following the following timeline.
The Ruler Pair for the new expiry will be created 2-5 days before the end of the expiry.
The rewards for the new expiry will start exactly 2 days (48 hours) before the end of the expiry. There maybe a gap of no more than 8 hours of no rewards). There may also be some rewards overlapping time.