Standard view and boardwalk view studios are generally not available at 7-months out year round, i.e., there is no such thing as an easiest time. Moreover, pool/garden view studios are usually gone before 7-months out throughout the high DVC high demand season at WDW, late Sep. through marathon weekend in Jan.
They also disappear before 7- months out for more than 50% of the rest of the year. Best chance to get one of those at 7-months out is likely during the lowest DVC demand times of the year. — July 7 to July 31, Feb 1 to the Thursday before Presidents’ Day, and last week of April.