In order to provide a seamless user experience around claiming yield farming rewards and avoid contention, each person's rewards are pre-allocated. There is a delay of 13 hours between when the rewards mature, and when they can be claimed because how much each person has earned would be unknown until that time.
A safe estimation would be to wait approximately 14 hours after your rewards are eligible to claim on the UI and then harvesting rewards. In order to prevent anyone losing their rewards, you will be unable to unlock through the UI until your rewards are ready to be claimed. Normally, this is 14 hours, but may be slightly longer if the Blockchain is highly congested.
Your rewards will NOT automatically harvest, and you will need to manually harvest them when the time comes. Auto-compounding is not in place and you will need to restake and start a new yield farming position. If you would like to take advantage of the compounding effect, you can easily take your SUNDAE rewards, deposit that as liquidity (with the equivalent amount of ADA) and start a new yield farming position.
If you can claim your rewards and restake your tokens by 23:59 UTC that same day, your farming rewards will act as if they are continuous, meaning you won't miss a day of rewards.