The strategic petroleum reserve has been decreasing since the closure of the Strait of Hormuz. It is now at 349 million barrels (compared to 415 million pre-war). When it will first see a week-on-week increase?

This market resolves based on the values officially reported by EIA - currently at 

https://www.eia.gov/petroleum/supply/weekly/

 under "Petroleum Balance Sheet". Directly at 

https://www.eia.gov/petroleum/supply/weekly/pdf/table1.pdf

 (will update if the source changes). Market resolves based on the date on the report that first reports a weekly increase (reports are typically published with a few days delay).

Some older historical trends below: (source: 

https://www.eia.gov/dnav/pet/hist/LeafHandler.ashx?n=pet&s=mcsstus1&f=m

, note that this is in thousands of barrels)