The current /datum/reading SolarQuery endpoint supports a few readingType query styles, but none of them support the situation when many nodes/sources are queried and the time range of available data per source varies more than the tolerance parameter. Increasing the tolerance can be done, but this has a negative impact on query performance. What's needed is a query style that can work without an explicit tolerance but still execute quickly.

Most likely this should be added as a new readingType so the existing queries are not impacted.