> The next expected block is always due in 10 minutes Not if the current network speed is higher than the difficulty level due to more mining power having come

> The next expected block is always due in 10 minutes Not if the current network speed is higher than the difficulty level due to more mining power having come online since the last difficulty change. You could estimate this by examining the block times over the last 120 (or some N) blocks, estimating the difficulty for that solve rate, and using the ratio of current network difficulty over the the estimated difficulty times 10 minutes.